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T 11 E A T I S K 



COLORING MATTERS DERIVED FROM COAL TAR. 



TREATISF. 



COLORING MATTERS DERIVED FROM 
COAL TAR; 

THEIR 

^practical Application in Ageing Cotton, SHcol, anb Silk. 



PRINCIPLES OF THE ART OF DYEING AND TIIE DISTILLATION 
OF COAL TAR. 

WITH A DESCRIPTION OF THE 

MOST IMPORTANT NEW DYES NOW IN USE, 



BY 

Professor H. DUSSAUCE, Chemist, 

Lately of the Laboratories of the French Government, viz., the Mining, 

Botanical Garden, the Imperial Manufacture of the Gohelins, the 

Conservatoire Impgriale of Arts and Manufactures, Professor 

of Industrial Chemistry to the Polytechnic Institute, 

Paris. 

*4> 



: PHILADELPHIA: 
HE/frRY CAREY BAIRD>,, 
INDUSTRIAL PUBLISHER, 

406* Walnut Street, 

1863. 



i ? 



9 



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A 



Entered according to Act of Congress, in the year 18C3, bj 

HENRY CAREY BAIRD, 

in the Clerk's Office of the District Court of the United States in 
and for the Eastern District of Pennsylvania. 



PHILADELPHIA : 
COLLINS, PRINTER. 



PREFACE. 



The object of this work is not to present 
to the public a treatise on the art of dyeing, 
but simply to furnish a full and clear de- 
scription of those colors concerning which 
so much is said and so little known. 

The greater part of the coloring matters 
employed by dyers, belongs to the vegetable, 
a few to the mineral, and fewer still to the 
animal kingdoms. Within a few years r 
a great variety of colors, among which are 
crimson, red, violet, blue, green, scarlet and 
yellow, have been obtained from a single sub- 
stance — coal tar — and the shades produced 
on silk and wool by these colors are unri- 
valled in beauty. 

As yet no distinct treatise on this subject 
has been published; all the information we 



VI PREFACE. 

have is found scattered here and there 
through many scientific and industrial publi- 
cations, and thus rendered almost inaccessible 
to the practitioner. Our object has been to 
collect these scattered items, and, in con- 
nection with our knowledge of the subject, 
prepare a practical work for the dyer and 
calico printer, authors having devoted them- 
selves more to the theory than the practice. 
The manipulations described in the different 
journals are difficult, and the great number of 
formulae used, render the explanation unin- 
telligible to any one not acquainted with 
chemical theories. We have endeavored to so 
simplify the recipes and minutely describe the 
manipulations as to enable any one, though 
not a chemist, to manufacture these colors. 
The principal works which we have consulted 
are : Les Comptes Rendus, Annates de Chimie 
et de Physique, Bulletin de la Societe d? encou- 
ragement, Moniteur industrkl, The Chemical 
News, London Journal of Pharmacy, Ameri- 
can Druggist 9 s Circular, etc. etc. 



PREFACE. Vll 

The book is divided into several chapters. 
The first is devoted to the general notions of 
the art of dyeing; several treat of the fabri- 
cation of colors of coal tar and their applica- 
tions ; and we terminate by the processes" to 
manufacture different new colors, and the 
theory of the fixation of colors and mordants. 

This work, the only one of the kind thus 
far published, we trust is destined to render 
great services to the dyer by removing the 
uncertainties now attending this new branch 
of industry, and enabling the dyer himself 
to manufacture those colors which he is now 
obliged to purchase at a very high price. 

The approbation of the profession will be 
our most satisfactory reward. 

THE AUTHOR. 

New Lebanon, N. Y., 

April, 1863. 



CONTENTS 



CHAPTER I. 

PAGE 

Historical notice of the art of dyeing . . . .25 

CHAPTER II. 
Chemical principles of the art of dyeing . . .33 

CHAPTER III. 
Preliminary preparation of stuffs 39 

CHAPTER IV. 
Mordants 43 

CHAPTER V. 
Dyeing . r 47 

CHAPTER VI. 
On the coloring matters produced by coal tar . . 49 

CHAPTER VII. 
Distillation of coal tar 52 

CHAPTER VIII. 

History of aniline — Properties of aniline— Preparation 
of aniline directly fron coal tar . . . .60 



f 



CONTENTS. 
CHAPTER IX. 

.Artificial preparation of aniline— Preparation of benzole 
— Properties of benzole — Preparation of nitro-benzole 
— Transformation [of nitro-benzole into aniline, by 
means of snlphide of ammonium ; by nascent hydro- 
gen ; by acetate of iron ; and by arsenite of potash 
— Properties of the bi-nitro-benzole .... 

CHAPTER X. 

Aniline purple — Violine — Roseine — Emeraldine — Bleu 
<le Paris . . . . . . . . w l 

CHAPTER XI. 
Futschine. or magenta 

CHAPTER XII. 

Coloring matters obtained by other bases from^coal tar 
— Nitroso-phenyline — Di-nitro-aniline — Nitro-pheny- 
line — Picric acid — Rosolic acid — Quinoline 

CHAPTER XIII. 

Naphthaline colors — Chloroxynaphthalic and perchlo- 
roxynaphthalic acids — Carruinaphtha — Ninaphthala- 
mine — Nitrosonaphthaline — Naphthamein — Tar red 
— Azuline . 

CHAPTER XIV. 

Application of coal tar colors to the art of dyeing and 
calico printing .112 

CHAPTER XV. 
Action of light on coloring matters from coal tar . .120 



CHAPTER XVI. 

PAGE 

Latest improvements in the art of dyeing — Chrysaniuiic 
acid — Molybdic and picric acids — Extract of madder 1 _ 

CHAPTER XVII. 

Theory of the fixation of coloring matters in dyeing and 
printing 133 

CHAPTER XVIIL 
Principles of the action of the most important mordants 144 

CHAPTER XIX. 
Aluminous mordants ...... 14- 

CHAPTER XX. 
Ferruginous mordants 

CHAPTER XXL 

Stanniferous morda- . 

CHAPTER XXII. 
Artificial alizarin . 175 

CHAPTER XXIII. 

Metallic hyposulphites as mordants — Dytjr'b soap — Pre- 
paration of indigo for dyeing and printing— Relati 
value of iudigo— Chinese green— Murexkk 



COLORING MATTERS FROM COAL TAR. 



CHAPTER I. 

HISTORICAL NOTICE OF THE ART OF DYEING. 

The art of Dyeing has been successfully prac- 
tised in the East Indies, Persia, Egypt, and Syria, 
from time immemorial. In the Pentateuch, fre- 
quent mention is made of linen cloths dyed blue, 
purple, and scarlet; and of ram skins dyed red; 
the works of the Tabernacle, and the vestments 
of the High Priest were commanded to be of pur- 
ple. 

The Tyrians were probably the only people of 
antiquity who made dyeing their chief occupation, 
and the staple of their commerce. The opulence 
of Tyre seems to have proceeded, in a great mea- 
sure, from the sale of its rich and durable purple. 
It is unanimously asserted by all writers, that a 
Tyrian was the inventor of the purple dye, about 
1500 years before the birth of Christ, and that 
the King of Phoenicia was so captivated with the 
3 



26 HISTORICAL NOTICE. 

color, that he made purple one of his prim 
ornaments, and that, for many centuries after, T y - 
rian purple became a badge of royalty. So highly 
prized was this color, that in the time of Augustus, 
a pound of wool dyed with it, cost at Rome, a sum 
nearly equal to thirty pounds sterling. The Ty- 
rian purple is now generally believed to have been 
derived from two different kinds of shell- fish, de- 
scribed by Pliny under the names purpura and 
buccinum ) and was extracted from a small vessel 
or sac in their throats to the amount of one drop 
from each animal; but an inferior substance was 
obtained by crushing the whole substance of the 
luccinum. At first it is a colorless liquid, but by 
exposure to air and light it assumes successively a 
citron-yellow, green, azure, red, and, in the course 
of forty-eight hours, a brilliant purple hue. If the 
liquid be evaporated to dryness soon after being 
collected, the residue does not become tinged in 
this manner. These circumstances correspond 
with the minute description of the manner of 
catching the purple-dye fish given in the work of 
an eye-witness, Eudocia Macrembolitissa, daughter 
of the Emperor Constantino the Eighth, who lived 
in the eleventh century. The color is remarkable 
for its durability. Plutarch observes, in his life 
of Alexander, that, at the taking of Susa, the 
Greeks found, in the royal treasury of Darius, a 
quantity of purple cloth, of the value of five thou- 
sand talents, which still retained its beauty, though 



HISTORICAL NOTICE. 27 

it had lain there one hundred and ninety years. 
This color resists the action even of alkalies, and 
most acids. 

Pliny states that the Tyrians gave the first 
ground of their purple dye by the unprepared 
liquor of the purpura^ and then improved or 
heightened it by the liquor of the buccinum. In 
this manner they prepared their double-dyed pur- 
ple — purpura dibapha — which was so called, either 
because it was immersed in two different liquors, 
or because it was first dyed in the wool and then 
in the yarn. 

In ancient Greece it does not appear that the 
art of dyeing was much cultivated. In Eome it 
received more attention; but very little is now- 
known of the processes followed by the Romans, 
such arts being held, by them, in low estimation. 
The principal ingredients used by these people 
were the following: Of vegetal matters, alkanet, 
archil, broom, madder, nutgalls, w r oad, and the 
seeds of the pomegranate, and of an Egyptian 
acacia; and of mineral productions, sulphate of 
iron, sulphate of copper, and a native alum mixed 
with the former. 

The progress of dyeing, as of all other arts, was 
completely stopped in Europe, for a considerable 
time, by the invasion of the Northern barbarians 
in the fifth century. In the East the art still con- 
tinued to flourish, but it did not revive in Europe 
until towards the end of the twelfth or the be^rin- 



28 HISTORICAL NOTICE. 

ning of the thirteenth century. One of the places 
chiefly celebrated for this art was Florence, where, 
it is said, there were no less than two hundred 
establishments at work in the early part of the 
fourteenth century. A Florentine dyer, having 
ascertained in the Levant a method of extracting 
a coloring principle from the lichens which furnish 
archil, introduced this on his return, and acquired 
by its sale an immense fortune. 

The discovery of America tended greatly to the 
advancement of this art, as the dyers were sup- 
plied thence with several valuable coloring mate- 
rials previously unknown; amongst which arc 
logwood, quercitron, Brazil-wood, cochineal, and 
annotto. About the year 16^0, also, a great im- 
provement in dyeing took place, which consisted 
in the introduction of a salt of tin as an occasional 
substitute for alum. With cochineal, the former 
was found to afford a color far surpassing in bril- 
liancy any of the ancient dyes. To Cornelius 
Drebbel the merit of this application is attributed. 
His son-in-law established an extensive dye-house 
at Bow, near London, about the year 15G3. 

For several centuries the Italians, and par- 
ticularly the Venetians, prosecuted the art of 
dyeing to a large extent, and long held a complete 
monopoly of the art, and procured large sums by 
it from other nations. In the year 1548, one John 
Ventura Eosetti published a book, termed Plictho's 
Art of Dyeing, in which he teaches how to give to 



HISTORICAL NOTICE. 29 

cloth, linen, cotton and silk, real and beautiful, 
as well as false and common dyes, which is, per- 
haps, the first book that ever appeared upon the- 
subject, and laid the first foundation for the im- 
provement of this art which afterwards took place; 
it having excited the French, English, and Germans 
to apply in earnest, in their different countries, to 
improving so useful and extensive a branch of 
manufacture. 

After this period the art was extensively carried 
on by the Flemings, and many of them emigrating 
to Germany, France, and England, established 
themselves as dyers, and thus gave great impetus 
to its advancement. In 1667, a Fleming named 
Brauer came to England with his whole family, 
and brought the dyeing of woollen there to that 
degree of perfection at which it has been ever since 
maintained. Shortly after this several works were 
published upon the art, which did much to im- 
prove it and make it more cultivated. 

Logwood and indigo began to be employed as 
dyes in Europe about the middle of the sixteenth 
century, but not without considerable opposition 
from the cultivators of the native woad ; the former 
were prohibited in England by Queen Elizabeth, 
under a very heavy penalty, and all found in the 
country was ordered to be destroyed: their use 
was not permitted till the reign of Charles the 
Second. 

Indigo, the innoxious and beautiful product of 
3* 



30 HISTORICAL NOTICE. 

an interesting tribe of tropical plants, which is 
adapted to form the most useful and substantial 
of all dyes, was actually denounced as a dangerous 
drug— food for the devil, it was called — and for- 
bidden by Parliament, in the reign of Elizabeth, 
to be used. An act was passed, authorizing 
searchers to burn both it and logwood in every 
dye-house where they could be found, and this 
act remained in full force till the time of Charles 
the Second, a period embracing a considerable £art 
of a century. A foreigner might have supposed 
that the legislators of England entertained such 
an affection for their native woad, with which 
their denuded sires used to stain their skins in 
the olden times, that they would allow no out- 
landish drug to come in competition with it. A 
most instructive and interesting volume might be 
written, illustrative of the evils inflicted upon arts, 
manufactures, and commerce, in consequence of 
the ignorance of lawgivers. 

When these absurd prejudices were gradually 
overcome in the eighteenth century, the art of 
dyeing made considerable progress. Madder, from 
which the color known as Turkey or Adrianople 
red is produced, then began to be properly appre- 
ciated; and quercitron, a fine yellow dye, was 
brought extensively into notice by Dr. Bancroft. 
But the chief improvements of the moderns in 
this art, consist in the employment of pure mor- 
dants, and in the application of colors derived 



HISTORICAL NOTICE. . 31 

from mineral compounds, as sesquioxide of iron, 
prussian-blue, chrome-yellow, chrome-orange, man- 
ganese-brown, etc. Each of these may be obtained 
as an insoluble precipitate, by mixing, together 
two dissolved salts; in the dyeing processes, the 
proper solutions are made to mingle, and produce 
the deposit within the fibre by impregnating first 
with one solution and afterwards with the other. 
As the precipitate thus produced is imprisoned 
within the fibre, it is not removable by mere 
aspersion with water. 

In India, was discovered the mode of dyeing 
Turkey red, which is the most durable vegetal 
tint known. It was afterwards practised in other 
parts of Asia and in Greece; and about the middle 
of last century, dye-works for this color were 
established near Eouen and in Languedoc by 
several Greeks. In 1765 the French government, 
convinced of the importance of the process, caused 
an account of it to be published; but it was not 
introduced into England until the end of the 
eighteenth century, when a Turkey -red dye-house 
was established in Manchester by M. Borelle, who 
obtained a grant from government for the disclo- 
sure of his process. The method, which was made 
public, does not seem to have been very successful. 
A better mode was introduced into Glasgow about 
the same time by another Frenchman, named 
Papillon. Previous to this, however, Mr. Wilson 
of Ainsworth, near Manchester, had obtained the 



32 HISTORICAL NOTICE. 

secret from the Greeks at Smyrna, which he re- 
vealed; but the process was said to be expensive, 
tedious, and less applicable to manufactured goods 
than to cotton in the skein. The greater part of 
the Turkey-red dyeing executed in Great Britain, 
is still carried on in Glasgow. 



THE ART OF DYEING. 33 



CHAPTER II. 

CHEMICAL PRINCIPLES OF THE ART OF DYEING. 

The art of dyeing has been of late so scientifi- 
cally cultivated that it would require a greater 
space than the limits of this treatise can afford, to 
give a complete idea of it, and we shall confine 
ourselves to the explanations of the chemical 
principles, on which are based the preliminary pre- 
parations of the textile fibres to render them fitted 
for the manufacture of tissue and those on which 
is founded the art of fastening coloring matters. 

Preparation of the Textile Fibres. 

The textile fibres used in manufactures are 
either of vegetable or animal origin ; the first 
being chiefly Hemp, Flax, and Cotton, and the 
second ivool, hair of animals, and silk spun by the 
silk worm. 

Cotton is nearly pure lignin, while hemp and 
flax are composed of lignin in long filaments, 
which, when dry, adhere to each other by means 
of a gelatinous substance called Pectin, although 
it differs probably from that found in fruits, and 
which must be removed to render them fit for 



34 THE ART OF DYEING. 

spinning and weaving. For this purpose they are 
rotted, which operation consists in plunging them 
tied in bundles, into water, where they are left, 
until fermentation commences, which is manifested 
in stagnant waters, by a very disagreeable odor ; 
the bundles are then withdrawn from the rotting 
pond, and, after having been dried in the air, are 
subjected to a mechanical operation of which the 
object is to detach the foreign substances, which 
have become friable by the desiccation ensuing on 
the rotting, and to isolate the fibres. Hemp and 
flax thus prepared are fit to be connected by 
spinning into unbleached thread, which may be 
immediately used for weaving cotton, undergoes 
no preliminary preparations, and may be imme- 
diately spun and woven. 

Wool, as it is found on the living animal, is im- 
pregnated with a considerable quantity of foreign 
matters, commonly called grease (suint), and which 
consists essentially of substances soluble in water, 
and fatty substances insoluble in that fluid. Sheep 
are usually washed before being shorn, and then 
yield what is called washed ivool, which has just 
lost a large portion of its soluble matters, and a 
portion of the fatty matters, which separated in 
the state of an emulsion. Wool which has not 
undergone this operation is called unwashed zcool, 
and the process by which the grease is removed 
from wool is known by the name of scouring. Un- 
washed is scoured with wash wool in a bath of S-i 



THE ART OF DYEING. 35 

gallons of water, and 20 to 22 gallons of putrefied 
urine, the whole being heated at 122° or 140° for 
soft wool, and to 158° or 167° for harsh wool; after 
dipping 6 lbs. 12 oz. or 9 lbs. of unwashed wool 
into the bath, and stirring it with a stick for 10 
minutes, they are removed and allowed to drain 
over the kettle, the same being done with another 
lot, until about 90 lbs. in all have been thus 
treated ; 1 J galls, to 2 galls, of putrid urine are 
then added, and 112 lbs. of washed wool passed 
through it, which is scoured both by the carbonate 
of ammonia of the putrefied urine and the alka- 
line substance yielded by the unwashed wool. 
The same operation is repeated on a new lot of 90 
lbs. of washed wool, after which a new dose of 1 J 
to 2 galls, of putrid urine is added, and 45 lbs. of 
unwashed wool, washed in it. This alternate 
scouring of wash and unwashed wool is continued 
during the whole day, adding urine at each fresh 
quantity of unwashed wool. After this operation 
the unwashed wool should be considered as wash^ 
and treated accordingly. 

When the wool scourer has no unwashed wool, 
he makes his bath of 183 galls, of water and 84 
galls, of urine, heats it at 120° or 140° and passes 
through it 68 lbs. of wool in 5 lots, each of which 
he leaves in the bath for 12 or 15 minutes, after 
which he adds 2 pints of water and \ gall, of 
urine, and then scours an additional portion of 68 



36 THE ART OF DYEING. 

lbs. of wool, &c. Some scourers add marly clay 
to the bath. 

"Wash wool contains less than 15 per cent, of 
grease, while unwashed contains much more, and 
by washing, scouring, and drying loses as much as 
60 or 70 per cent, of its weight. When the washed 
wool contains less than 5 per cent, of grease, 
it is scoured with soap or carbonate of soda. 

The nature of the fatty matters of the grease is 
peculiar, and they have been called by Mr. Chev- 
reul stearerin and elaierin ; the first is solid, but 
uncrystallizable, the second is oleaginous. These 
fats are not saponified by weak alkalies, but when 
they are boiled for a long time with a solution of 
caustic potash, the liquid is found to contain two 
salts of potash, formed by peculiar fat acids which 
have been called steareric and claieric acids, while 
nothing analogous to glycerin has been found, the 
oxygen of the air may possibly have some share 
in the formation of these fat acids. 

After scouring, the wool is washed in river 
water, in willow baskets. When it is intended to 
be perfectly white, it is exposed for some time in 
a moist state in rooms in which sulphur is burned, 
where the sulphurous acid finishes the bleaching, 
and the excess of it is removed by fresh washings. 
It is important not to prolong too much the action 
of the sulphurous acid, because it exerts a decom- 
posing agency on the nitrogenous substance of the 
wool. 



THE ART OF DYEING. 37 

Wool contains a proximate sulphuretted prin- 
ciple, which may be separated by successive 
immersions in lime-water. Wool which has 
been heated with a weak alkaline solution, disen- 
gages sulphydric acid, when it is again heated 
with acidulated water, and is blackened when 
boiled with a solution of a salt of lead or prot- 
oxide of tin. 

Raw Silk) as obtained from the cocoons, is im- 
pregnated with a gelatinous substance, which 
makes it very stiff, and generally gives it a golden 
yellow tinge. This substance, which forms about 
\t\ of the weight of raw silk, dissolves readily in 
alkaline liquids, but as caustic alkalies attack the 
silk itself, soap is almost always used, and some* 
times, but rarely, carbonate of soda. 

The operation which is called Scouring (De- 
CREUSAGe) the silk, is divided into three stages, the 
ungumming (DEGOMMAGE), boiling, and bleaching. 
The ungumming is done in a tin boiler containing 
for every 100 parts of silk, 1800 or 2500 parts of 
water, and 30 of soap. It is first boiled to dissolve 
the soap, and then cold water is added so as to 
lower the temperature at about 200°, when the 
silk is dipped into it in skeins, supported by sticks 
called^ lisoirs, being there left until all the gelati- 
nous matter is dissolved, and afterwards wound 
on a bobbin. This operation lasts from § to 1J 
hours. Several skeins are then united, forming a 
hank, which is boiled for 1J hours in a bath con- 
4 



38 



THE ART OF DYEING. 



taming 20 or 30 parts of soap for 2000 parts of 
water, which constitute the boiling (Cuite). The 
hanks are undone, twisted into skeins, wound on 
a bobbin, and then washed in a weak solution of 
carbonate of soda, and in water. The bleaching 
consists in dipping the silk held by the lisoirs, 
into a bath heated at 203°, and composed of 
84 galls, of water, and from 1 lb. 2 oz. to 1 lb. 12 
oz. of white Marseilles soap. Silks which are in- 
tended to be white, are exposed in addition to 
sulphurous acid. 



PREPARATION OF STUFFS. 39 



CHAPTER III. 

PRELIMINARY PREPARATION OF STUFFS. 

Before being printed, cotton stuffs are singed 
with the intention of removing the filaments 
which project from the tissue. The shearing is 
performed by machines called shearing machines, 
composed of two revolving cylinders, one of 
which, furnished with brushes, raises the nap, 
while the other, provided with knives arranged 
spirally, shears it. In singing, the stuff is passed 
rapidly over a metallic cylinder, heated to nearly 
a white heat, which burns off the down. Cotton 
stuffs intended to be perfectly white, are previously 
bleached, which operation is also more or less 
completely performed on goods which are to be 
printed. 

Linen and cotton goods are bleached by two 
processes : 1. By washing them in alkaline lyes, 
and exposing them on the grass. 2. By chlorine 
and by the alkaline hypochlorites. 

The first is the oldest, and was used par- 
ticularly for bleaching flax and hemp goods. It 
is divided into the following operations : 1. Scour- 
ing, which consists in dipping the stuffs for twenty- 



40 PREPARATION OF STUFFS. 

four hours in a weak solution of caustic potash, 
heated at about 99°, washing, and then boiling 
them for twenty minutes in the same alkaline 
lye. 

2. The boiling, which consists in boiling the 
scoured stuffs, after having washed them in water, 
and compressed them between cylinders. 

3. Bleaching, which consists in boiling them for 
six hours with an alkaline lye containing 1 part 
of caustic potash for 16 parts of stuff, washing 
them, and exposing them for five or six hours on 
the grass; the alkaline washings and exposure on 
the grass being renewed until the stuffs are per- 
fectly bleached. During the exposure on the 
grass, the coloring matters are bleached by the 
influence of the solar rays and moisture; the 
absorption of oxygen converting them into new 
substances, more readily soluble in the alkaline 
liquors. Lastly, the stuffs are passed through 
water heated at 105° or 120°, containing about 
e 1 of sulphuric acid, which dissolves the metallic 
oxides, after which they are washed and calen- 
dered. 

This process requires a great length of time, 
and bleaching by the hypochlorites or chlorine 
is more expeditious. The chlorine acting on the 
coloring matter in the presence of the water, de- 
composes this water into hydrogen and oxygen ; 
hydrogen combines with the chlorine to form 
hydrochloric acid, while oxygen in the nascent 



PREPARATION OF STUFFS. 41 

state oxidizes the resinous and coloring matters, 
and renders them soluble in alkaline lyes. The 
hypochlorites are reduced to the state of chlo- 
rides, and act at the same time by means of the 
nascent oxygen given off by the hypochlorous acid 
and the base, while the concurrence of an acid 
effecting the decomposition of the hypochlorites 
hastens the bleaching. Thus in both processes it 
is in the end always an oxidizing action, which 
effects the bleaching and destruction of the foreign 
substances. 

Hypochlorite of lime, dissolved in water, is 
now solely used in bleaching, and it is preferable 
to all dilute solutions, because it is less liable to 
injure the ligneous fibre of the tissue, although 
the bleaching then requires more time. 

The stuffs, after being passed over the heated 
cylinder to be singed, are immediately dipped 
into a vat filled with water to cool them, where 
they then remain for twenty-four hours, and lose 
a considerable portion of their soluble principles. 
They are then to be perfectly dried, either by 
being beaten or compressed between cylinders, 
and then kept for twelve hours in a vat filled 
with water heated by steam, where they are 
arranged in alternate layers with slaked lime; 
after being again beaten, they are left for twelve 
hours in a lye of caustic soda, consisting for 300 
parts of stuffs, of 10 parts of caustic soda for 
1500 of water. This lye is replaced by another 

4* 



42 PREPARATION OF STUFFS. 

containing only 7.5 of soda, which is also allowed 
to act for twelve hours ; after which the stuffs, 
pressed dry, are passed through the hypochlorite 
of lime, and then through sulphuric acid. The 
bath of hypochlorite generally contains 0.15 
parts of chlorine or a quart of water ; and the 
stuffs after being immersed in it are passed be- 
tween two wooden cylinders, descending them 
immediately into a bath acidulated with sulpliuric 
or hydrochloric acid, which hastens the bleaching 
by isolating the hypochlorous acid. 

After being washed in fresh water, they are for 
a second time subjected to the action of alkaline 
lyes, hypochloride of lime, and the acid baths, and 
lastly, after another washing in fresh water, they 
are dried in washing machines, and more body is 
given to them by dressing them with starch. 



MORDANTS. 43 



CHAPTER IV. 

MORDANTS. 

The tissues of muslin or linen stuffs have, for 
a great number of coloring substances, an affinity 
sufficiently powerful to fasten them on their sur- 
faces, and to acquire a deep color, while the com- 
bination is nearly strong enough to enable them 
to resist washing; particularly with alkaline soaps. 
They are made fast, and at the same time the 
color is heightened by previously depositing on 
the tissues certain substances which have a greater 
affinity for these tissues than the coloring matter, 
and which possess, at the same time, the pro- 
perty of forming, with the coloring matters, com- 
pounds sufficiently fixed to resist washing in fresh 
water and in soapsuds. These substances which 
thus play an intermediate part between the woven 
fabrics and the coloring matters, are called mor- 
dants. The affinities, by virtue of which they are 
fastened on the fabric, exhibit this essential dif- 
ference from those observed in ordinary chemical 
operations, that, in the latter, combination gene- 
rally ensues only between disaggregated sub- 
stances, and if one of the substances is originally 



44 MORDANTS. 

aggregated, it becomes disaggregated by the 
simple fact of combination ; while, in dyeing, the 
woven fabric retains its form and consistence, 
without being in the slightest degree disaggre- 
gated by the mordants and coloring matters. 
Certain mordants do not change the shade of the 
coloring matters, such, for example, as the salts 
of alumina and chloride of tin; while others, 
on the contrary, alter the color, as the salts of 
iron, copper, manganese. The salts of alumina, 
used as mordants, are the sulphate and acetate of 
alumina and alum ; the fastening of color by alum 
being called aluming. 

In order to alum cotton, flax, or hempen stuffy 
they are left for twenty-four hours in a tepid bath, 
containing one pound of alum for six pounds of 
fabric, when a portion of the alum adhering to 
the stuff, renders the latter fit for dyeing. For 
dark colors, the ordinary commercial alum is 
used ; pure alum being preferred for bright colors, 
because common alum contains a small quantity 
of sulphate of iron, which would modify the 
color. 

Wool is alumed by being first boiled in bran- 
water for an hour, and washed in fresh water, and 
then kept for two hours in a boiling solution 
which contains ten to fifteen per cent, of alum, a 
small quantity of cream of tartar being generally 
added, which facilitates the deposit of alumina on 
the tissue, probably in converting a portion of the 



MORDANTS. 45 

sulphate of alumina into a tartrate more easy to 
decompose. When the wool is alumed, it is left 
for two days to rest before dyeing, in order to 
render the combination of the mordant with the 
fibre more intimate. 

Silk is alumed when cold, by keeping it for 
fifteen or sixteen hours in a bath containing ^ of 
alum, after which it is removed and washed. 
Acetate of alumina, which is often used as a mor- 
dant for ligneous stuffs, and for certain colors, is 
prepared like we shall see hereafter, by decom- 
posing alum by acetate of lead. The solution of 
acetate of alumina thus obtained being generally 
thickened with gum or starch. 

Stuffs of lignin, mordanted with alum, are 
again subjected, before being dyed, to another 
operation, the effect of which is not well under- 
stood; they are immersed for some time in two 
baths of water, containing from six to eight per 
cent, of cow-dung. To the first of these baths a 
certain quantity of chalk is added, the intention of 
which appears to be to saturate the acid partly 
adhering to the tissue with the mordant; while 
the second contains only water and dung. The 
temperature of these two baths varies according 
to the nature of the stuffs and that of the mor- 
dants. The cow-dung appears to act by means 
of the phosphates it contains, for a mixture of 
phosphate of soda and lime can be substituted 
for it. 



46 MORDANTS. 

Protochloride of tin is chiefly used for obtain- 
ing the oxide of tin as a mordant, which adheres 
very firmly to the tissues. Bichloride of tin is 
often used for freshing colors, particularly those 
of cochineal and madder. 

The mordant of oxide of iron is furnished by 
the proto-acetate, prepared by the action of pyro- 
ligneous acid on old iron. 

The question of mordants is so important, that 
we will treat it hereafter at some length. 



DYEING. 47 



CHAPTER V. 

DYEING. 

After the stuffs are mordanted, they are .im- 
mersed in order to be dyed, in solutions of color- 
ing matters of various temperatures, and then 
left for a longer or shorter time, according to the 
nature of the stuff and the tint of color to be 
obtained. It is essential that all parts of the fabric 
should remain the same length of time in the dye; 
to which effect it is rolled around a wooden roller 
suspended under the dye tub, and is unrolled 
through the tub, this process being continued 
until the color has obtained the shade required. 
In order to obtain a regular shade, it is better to 
use successive baths of different strength, com- 
mencing with the weakest. The baths are some- 
times composed of a single coloring matter, and 
sometimes of a mixture of several, while at other 
times the stuff is passed successively through two 
baths containing different colors, and thus an in- 
termediate shade is obtained ; the colors are fast- 
ened by washing in soapsuds or in other solutions. 



48 DYEING. 

It would lead us too far to give a description of 
the methods of preparing the different solutions 
for dyeing and the manipulations of the process. 
For this we refer the reader to a regular work on 
the art of dyeing. 



COLORING MATTERS PRODUCED BY COAL TAR. 49 



CHAPTER VI. 

ON THE COLORING MATTERS PRODUCED BY COAL 

TAR. 

History, — Until the year 1854, Aniline was 
known only by chemists; it was a product of the 
laboratory which was found only with difficulty; 
still, Industry had not the less desire to use it, on 
account of its high price and its difficult and costly 
preparation. At that time, Mr. Dumas presented 
to the Academy of Science of Paris a paper on a 
new method of formation of artificial organic bases, in 
which Mr. Bechamp made known a process by 
which he was enabled to obtain Aniline not only 
easily, but also at a low price. 

By the efforts of Messrs. Kenard Brothers, Franc, 
Tabourin and Bechamp, Aniline is now a product 
which can be obtained easily. 

In 1826, Unverdorben, studying the products 
which result from the dry distillation of animal 
matters with indigo, discovered among the pyro- 
geneous products of this last substance, an organic 
basis, volatile, liquid, and heavier than water, 
which he called Crystalline, because with mineral 
acids it produces easily crystallized salts. 
5 



50 COLORING MATTERS PRODUCED BY COAL TAR. 

Mr. Fritzsche afterwards studied these products, 
and called Aniline (from the name of the indigofera 
anil) the basis obtained in distilling indigo with 
caustic potash. He demonstrated that this basis 
was identical to Crystalline. Subsequently Mr. 
Eunge isolated, by a process modified by Hoffmann, 
among the bases which exist in the heavy oils of 
the distillation of coal tar, an oily organic basis 
from which he developed a fine violet blue color 
by hypochlorite of lime. 

Mr. Zinin afterwards, by the action of sulphuret 
hydrogen on nitro-benzinc in connection with 
ammonia, produced an organic basis which he 
called Jl //-/'A///?. 

AVhen the identity of all these products was 
established, chemists adopted the name of An> 
to designate them all, this title being the best for 
the formation of compound names. 

These first experiments gave birth to others 
which showed that in a multitude of reactions, 
Aniline could be produced, so it could be formed 
by the action of alkalies and alcohol on nitro- 
benzine. 

Messrs. Laurent and Hoffmann, in heating for 
fifteen days, in a tube, pha uic acid with ammonia, 
have also produced Aniline. 

During all the time that this product could be 
made only by the above processes, Aniline was 
simply an object of curiosity. Its extraction from 



COLORING MATTERS PRODUCED BY COAL TAR, 51 

coal tar was difficult, and from indigo, the quantity 
produced was too small and too costly. 

Mr. Perkins, the great English manufacturer, 
studied the production of Aniline at the same time 
as several French chemists, but the French being 
too much engaged with the theoretical question, 
left to Mr. Perkins the honor of the industrial dis- 
covery. It was with the benzine (benzole) that 
he succeeded in producing the largest quantities 
of Aniline. 



52 DISTILLATION OF COAL TAR. 



CHAPTER VII. 

DISTILLATION OF COAL TAR. 

The dry distillation of organic matters, vege- 
table or animal, from the great variety of products 
to which it gives rise, constitutes one of the most 
interesting operations of chemistry. 

Their reactions are very complex, and some of 
them have been very little studied, as indeed is 
the case with many of the substances formed. 

If the body submitted to dry distillation could 
be maintained during the operation under uniform 
conditions of desiccation, temperature, and pr 
sure, the reactions and the products would be 
more simple. ]f, for example, wood be heated 
very slowly in close vessels, first to 212° 1\, then 
to 892° and 572°, and so on, there is at first dis- 
engaged almost pure water, then impure strong 
acetic acid, and afterwards a mixture of acetone 
and acetate of methylene; the maximum of char- 
coal is left as residue, and the least amount of tar 
and gas is produced, the latter consisting only of 
carbonic acid and carburetted hydrogen. 

In practice, however, when wood is distilled in 
iron cylinders, heated from the outside, the heat 



DISTILLATION OF COAL TAR. 53 

only penetrates to the interior gradually. The 
outside layers are, therefore, the first decomposed; 
they at first lose water, then furnish pyroligneous 
acid and wood spirit, at the same time giving off 
carbonic acid and a little carbu retted hydrogen. 

The inner layers in turn are similarly decom- 
posed, but the products as they are given off are 
brought into contact with the outer layer, already 
in a more advanced state of decomposition and at 
a much higher temperature, and hence new reac- 
tions take place and new products are formed. 
Thus, the vapor of water in contact with red hot 
charcoal is decomposed, and forms carbonic acid 
and hydrogen; a part of the carbonic acid is again 
decomposed by the red hot carbon to form some 
oxide of carbon. A part of the nascent hydrogen 
combines with carbon to form various hydro- 
carbons; one part of the acetic acid is decomposed 
by the high temperature to form acetone and car- 
bonic acid; another part reacts on the wood spirit, 
and forms methylic acetate; a fraction of the wood 
spirit and acetone are also decomposed, producing 
tarry matters, pyroxanthine, oxyphcnic acid, duma- 
sine, etc. To these must be added the influence 
of certain nitrogenized bodies, and we can under- 
stand how all these compounds, successively 
formed under the most favorable circumstances 
for acting on one another, since Vaej are in the 
nascent state and exposed to a high temperature, 
may give rise to the formation of a great variety 



54 DISTILLATION OF COAL TAR. 

of different compounds, which will be set free 
either in the state of a permanent gas or of a 
condensable vapor, and leave fixed carbon as a 
residue. 

The same takes place whether wood, coal, 
asphalte, peat, resin, oils, or animal matters be 
distilled; but it is evident that the original com- 
position of the material submitted to dry distilla- 
tion must powerfully influence the nature and 
composition of the products. In those which, 
like wood, are rich in oxygen and poor in nitro- 
gen, the pyrogeneous products contain much 
acetic acid and but little ammonia, and conse- 
quently have an acid reaction; on the contrary, 
the matters containing much nitrogen, and but 
little oxygen, like coal and animal matters, give 
rise to the formation of much ammonia, and the 
products have an alkaline reaction. 

In this division we intend only to confine our 
attention to the products obtained by the distillo 
tion of coal tar from gas works. Considerable 
differences are noticed in the composition of the 
tar procured from different qualities of coal and 
schists, according to the rapidity with which the 
distillation has been conducted. Some tars, for 
instance, contain but little benzole, but much 
naphthaline; boghead tar is rich in paraffine; 
others contain a preponderating quantity of 
phenyl and benzole. 



DISTILLATION OF COAL TAB. 



55 



Table of the Products Obtained by Distillation and 

Rectification of Coal Tar. 

Solid Products. 



Carbon, 


or Anthraceine, 


Chrysene, 


Naphthaline, 


Paraffin e, 


Pyrene. 


Paranaphthaline 






, 


Liquid Products. 




Acids. 


Neutrals. 


Bases. 


Rosolic, 


Water, 


Ammonia, 


Brunolic, 


Essence of Tar, 


Methylamine, 


Phenic, 


Light Oil of Tar, 


Ethylamine, 


Phenol, 


Heavy Oil of Tar, 


Aniline, 


Acetic, 


Benzole, 


Quinoline, 


Buthyric. 


Toluole, 


Picoline, 


- 


Cumole, 


Toluidine, 




Cymole, 


Lutidine, 




Propyle, 


Cumidine, 




Butyle, 


Pyrrhol, 




Amyle, 


Poetinine. 




Caproyle, 






Heptylene, 






Hexylene. 






Gaseous Products. 





Hydrogen, Various Hydro-Car- Carbonic Acid, 

Carburetted Hydro- bides, Sulphydric Acid, 

gen, Oxide of Carbon, Hydrocyanic Acid. 

Bicarburetted Hy- Sulphuret of Car- 

drogen, bon, 

Whatever may be the composition of the dif- 
ferent kinds of tar, they are all submitted to dis- 
tillation in order to isolate the principles capable 
of industrial application. But, first of all, it is 



50 DISTILLATION OF COAL TAR. 

necessary to separate the tar, as far as possible, 
from the ammoniacal liquor which is found with 
it. For this purpose, it is heated some hours at 
176° or 212° F., by which it is rendered more 
liquid, and then the water separates more easily. 
It is then allowed to cool very slowly, and the 
water is drawn off by a tap placed at the lower 
part of the boiler. A certain quantity of tar 
obstinately retains the water, constituting a 
buttery matter, whicb may be allowed to run 
away with the water, to be added afterwards to 
another quantity of tar to be deahydrated by a 
fresh operation. 

Experience seems to have demonstrated that 
the most simple process, that is to say, distillation 
over a naked fire at the ordinary pressure, is still 
the most practicable and advantageous. As the 
volatile products have but little latent heat, the 
height of the still should be somewhat less than 
the diameter; for the same reason the head must 
be carefully protected from cold, and it is well to 
furnish the inside with a circular gutter, in which 
the products condensed in the head may be col- 
lected and run into the refrigerator. By this 
means the products are prevented from flowing 
back into the boiling tar, and being decomposed 
by coming in contact with the sides of the still, 
which, especially towards the end of the operation, 
becomes very hot. 

In condensing the vapors, it is necessary to 



DISTILLATION OF COAL TAR. 57 

observe certain precautions. At the beginning, 
of the operation, when the lighter and more 
volatile oils are passing, the worm must be well 
cooled to make quite sure of the condensation. 
Later, when the heavier and less volatile products 
are coming over, the water in the refrigerator 
may be allowed to get heated at 86° or 104° P., 
and at last when the matters capable of solidi- 
fying, such as naphthaline and paraffine, pass, 
the temperature of the refrigerator should never 
be under 104° P., and it may be allowed without 
inconvenience to raise to 140° or 158° F. At 
this temperature the products condense perfectly, 
but remain liquid and run with ease. If the 
refrigerator was kept quite cold during the whole 
process, it might happen toward the end, that the 
condensed tube would become blocked up by the 
solidified products, and a dangerous explosion 
might ensue. 

At the beginning of the distillation the tar 
should not be allowed to boil too fast. Some dis- 
tillers at this period pass a current of steam at 
230° or 248° F., through the tar to assist the dis- 
engagement of the more volatile oils. 

These, in condensing, form a very limpid fluid 
liquid, having the density of .780, which gradually 
rise to .850 ; the mean density of all the products 
united is about .830. It is this, which constitutes 
the benzine of commerce. It contains a great 
variety of compounds whose boiling points range 



58 



DISTILLATION OF COAL TAR. 



from 140° to 392°. They belong to the following 



series : — 



O H n e. g. 



Amylene, C 5 II 5 

Hexylene (oleine Caproylene) 

Hepthylene (Oenenthylene) 



C n H n + 2 e. g. Propyle 
Butyle 
Amyle 

C u H° — G c. rj. Benzine 



C 6 H* 
C 7 H 7 

etc. 
C 12 II' 4 

C 1G Q | 

etc. 
C" II G 



When the density of the products exceeds 
.850, the current of steam is stopped and the heat 
increased. As soon as the temperature of the tar 
has risen from 31)2° to 428° 1\, the distillation re- 
commences, and the oil condensed is found to have 
a sp. gr. .860 to .900, the mean being from .880 to 
.885. This product constitutes the heavy oil of 
tar, and contains phenol, creasote, and aniline. 

Lastly, the ultimate products of the distillation, 
which on cooling become a buttery mass, or crys- 
talline, if they contain much naphthaline, are 
set aside for the preparation of paraffine. They 
are placed in vats, which are cooled, in order that 
the solid matters may separate by crystallization. 

2000 parts of rough oil of tar obtained by the 
distillation of Boghead coal furnished on rectifi- 
cation : — 



DISTILLATION OF COAL TAR. 59 

1208 parts light oil, density = .825 
200 " heavy oil = . . .860 
400 " pitch 
192 " gas escaped 

2900 parts of tar from gas works using Boghead 
coal, distilled in a similar manner, yielded : — 

Water, slightly amrooniacal .... 168 

Light hydro-carbons, mean density .820 . . 480 

Heavy hydro- carbons, mean density, .863 . 883 

Fatty pitch, solid when cold, liquid at 302° F. 1195 

Loss 6 per cent 174 

2900 



60 HISTORY OF ANILINE. 



CHAPTER VIIL 

HISTORY OF ANILINE— PROPERTIES OF ANILINE — 
PREPARATION OF ANILINE DIRECTLY FROM COAL 
TAR. 

§ 1. History of Anili\ 

Aniline was discovered in 1826 by Unverdor- 
ben. The original method for its preparation was 
by digesting indigo with hydrate of potash, and 
subjecting the resulting product to distillation. 
Aniline was also obtained from the basic oils of 
coal tar; but the process which is now employed 
for its preparation is a remarkable instance of the 
manner in which abstract scientific research be- 
comes, in the course of time, of the most import- 
ant practical service. It was Faraday who first dis- 
covered benzole; he found it in oil-gas. After this 
it was obtained by distilling benzoic acid with 
baryta, which result determined its formula, and 
was the cause of its being called benzole. After 
this, Mansfield found it to exist in large quantities 
in common coal tar naphtha, which is the source 
from which it is now obtained in very large quan- 
tities. Benzole, when studied in the laboratory, 
was found to yield, under the influence of nitric 



HISTORY OF ANILINE. 61 

acid, nitro-benzole. Zinin afterwards discovered 
the remarkable reaction which sulphide of ammo- 
nium exerts upon nitro-benzole, converting it into 
aniline. And, lastly, Bechamp found that nitro- 
benzole was converted into aniline when submit- 
ted to the action of ferrous acetate. It is Be- 
champ's process which is now employed for the 
preparation of aniline by the tun. Had it not 
been for the investigations briefly cited above, the 
beautiful aniline colors now so extensively em- 
ployed, would still remain unknown. When Mr. 
Perkins discovered aniline purple, nitro-benzole 
and aniline were only to be met with in the labo- 
ratory ; in fact, half a pound of aniline was then 
esteemed quite a treasure, and it was not until a 
great deal of time and money had been expended 
that he succeeded in obtaining this substance in 
large quantities, and at a price sufficiently low for 
commercial purposes. 

The coloring matters obtained from aniline are 
numerous; they are the following: Aniline purple, 
violine, roseine, futschine, alpha aniline purple, 
bleu de Paris, nitroso-phenyline dinitraniline, and 
nitro-phenyline diamine. 

§ 2. Chemical Properties of Aniline. 

Pure aniline is a colorless liquid, very astrin- 
gent, having an aromatic odor and an acid burning 
taste, slightly soluble in water, very soluble in 
alcohol and ether. 
6 



62 HISTORY OF ANILINE. 

Its specific gravity =1.028. It does not freeze 
at —20. 

It boils at 262°.4 F. ? and distils unchanged. 
When warmed it dissolves sulphur and phosphorus. 

It is a powerful basis, combining with acids, 
and forming salts, which in general are soluble. 

It decomposes salts of protoxide and peroxide 
of iron, and the salts of zinc and alumina, preci- 
pitating from them the metallic oxides. 

It precipitates also the chlorides of mercury, 
platinum, gold, and palladium, but does not pre- 
cipitate the nitrates of mercury and silver. 

Aniline easily oxidizes, turning yellow in water, 
and in time becoming resinified. 

When aniline dissolved in hydrochloric acid is 
acted on by chlorine, the solution takes a violet 
color, and on continuing the current of chlorine, 
the liquid becomes turbid and deposits a brown- 
colored resinoid mass. In distilling the whole, 
vapors of trichloramh'nc and trichloroj'hcnic acid 
pass over, t 

A solution of the alkaline hypochlorites colors 
aniline violet blue, which turns rapidly red, espe- 
cially in contact with acids. 

A mixture of hydrochloric acid and chlorate of 
potash acts on aniline, the final result of the action 
being chloranilc C 12 CI 4 O 4 , but in the course of the 
reaction several colored intermediary bodies are 
formed. 

If a solution of chlorate of potash in hydro- 



HISTORY OF ANILINE. 63 

chloric acid be added to a solution of a salt of 
aniline mixed with an equal volume of alcohol, 
and care is taken to avoid an excess of the hydro- 
chloric solution, a flocculent precipitate is deposited 
after a time of a beautiful indigo blue color; this 
precipitate filtered and washed with alcohol con- 
•tracts strongly, and passes to a deep green. The 
filtered liquid has a brownish red color ; on boil- 
ing it, adding fresh quantities of hydrochloric 
acid and chlorate of potash, a yellow liquor is 
obtained, which deposits crystallized scales of 
chlor anile. 

An aqueous solution of chromic acid gives, w r ith 
solutions of aniline, a green, blue, or black pre- 
cipitate, according to the concentration of the 
liquors. 

When a small quantity of an aniline salt is 
mixed in a porcelain dish with a few drops of 
strong sulphuric acid, and a drop of a solution of 
bichromate of potash is allowed to fall on the 
mixture, a beautiful blue color appears after some 
minutes, which, however, soon disappears. 

Diluted nitric acid combines with aniline with- 
out adhering to it immediately ; but after some 
time nitrate of aniline crystallizes in the form of 
concentric needles, the mother liquor turns red 
colored, and the sides of the evaporating dish 
become covered with a beautiful blue effer- 
vescence. When a few drops of strong nitric acid 
are poured upon aniline, it is immediately colored 



64 HISTORY OF ANILINE. 

a deep blue; on applying heat the blue tint quickly 
passes to yellow, a lively reaction is manifested, 
which results in the formation of picric acid, or 
trinitrophenisic acid. 

Potassium dissolves in aniline, disengaging 
hydrogen, whilst all becomes a velvet-colored pap. 

The other reactions of aniline which are cha- 
racterized by the formation of Futschine Aza- 
leine, will be related in the sequel of this book, 
when describing their preparations. 

§ 3. Preparation of Aniline directly from Coal Tar. 

The method which appears to be the most ra- 
tional, and which deserves to be tried, would consist 
in. treating the tar as condensed in gas works with 
hydrochloric or sulphuric acid, diluted with three 
or four times its volume of water. Mechanical 
means for affecting the intimate mixture of the 
tar with the acid might be easily contrived, but 
in the absence of any special contrivance, the end 
may be obtained by half filling a barrel with the 
tar, adding one-fifth or one-sixth of its volume of 
acid, and rolling and shaking the barrel until the 
acid has taken up the bodies with which it is able 
to combine; the whole might thus be run into a 
cistern, where, by degrees, the watery liquid would 
separate from the tar. 

The same acid liquid might be used over and 
over again until the bases have nearly saturated 
the acid. A very impure aqueous solution would 



HISTORY OF AXILIXE. 65 

thus be obtained, containing the hydrochlorates 
or sulphates of ammonia, and all the other organic 
bases contained in the tar, such as aniline, quino- 
line, pyrrol, picoline, pyrrhidine, lutidine, ioluidine ) 
curnidine, etc. 

By evaporating this solution almost to dryness, 
and then distilling with an excess of milk of lime, 
the bases would be set at liberty. Ammonia, as 
the most volatile, would be disengaged first, and 
might be condensed apart, and by raising the tem- 
perature higher and higher, the organic bases 
would be disengaged. Aniline would be found 
among the liquids distilling between 302° and 
: F. 

The manipulation of the tar, however, is an 
extremely disagreeable operation, and presents 
many difficulties; it is therefore preferable, in 
man}' cases, to distil the tar first, and operate on 
the most pure and limpid distilled oil. 

Aniline, because of its high boiling point, is 
never met with, in the light and volatile liquids 
when first distilled from tar. The most of it is 
found in those which distil between 302 and 356.° 
These, according to Hoffmann, contain about 10 
per cent, of organic bases, mostly aniline and quino- 
line. The oils which distil above 482°, contain 
mostly quinoline and very little aniline. 

The- following process for extracting the two 
bases from the oil and separating them, is due to 
Hoffmann. The oil is agitated strongly with com- 

6* 



66 HISTORY OF ANILINE. 

mercial hydrochloric acid. The mixture is then 
allowed to rest for 12 or 14 hours, and the oil is 
separated from the acid; the latter is treated again 
by fresh quantities of oil until nearly saturated. 
The still acid solution is filtered to retain the oil 
interposed mechanically. It is then placed in a 
copper still and supersaturated with an excess of 
milk of lime. At the moment of saturation an 
abundance of vapors are given off, and the head 
must be quickly fixed on the still. TIeat is now 
applied so as to obtain a quick and regular ebulli- 
tion. 

The condensed product is a milky liquid with 
oily drops floating on it. The distillation is car- 
ried on, as long as the vapor has the peculiar odor 
of the first part distilled, or the condensed product 
gives the characteristic reaction of aniline with 
chloride of lime. 

The milky liquid is now saturated with hydro- 
chloric acid ; it is then concentrated in a water 
bath ; and lastly, decomposed in a tall narrow ves- 
sel by means of a slight excess of hydrate of pot- 
ash or soda. The bases set free, unite and form 
an oily liquid, which floats on the alkaline solu- 
tion. This is removed with a pipette and rectified. 
The rectified product is aniline, sufficiently pure 
for industrial purposes, especially if we set aside 
the part distilling above 392° or 428° F., which is 
principally composed of quinoline. 

To obtain aniline chemically pure, the neutral 



HISTORY OF ANILINE. 67 

oils forming part of the oily layer must be com- 
pletely removed. This is done by dissolving the 
whole in ether, and adding dilute hydrochloric 
acid, which combines with and separates the bases, 
and leaves the oil in solution in ether. The acid 
solution is then decanted, decomposed with pot- 
ash, and submitted to careful fractional distillation. 
If the products are gathered separately in three 
parts, the first will contain ammonia, water, and 
some aniline; the second will be pure aniline; while 
the third portion will contain mostly quinoline. 
An alcoholic solution of oxalic acid is now added 
to the impure aniline, which precipitates oxalate 
of aniline, as a mass of white crystals, which are 
washed with alcohol, and then pressed. The salt 
is then dissolved in a small quantity of water, to 
which a little alcohol is added. From this solu- 
tion, the oxalate crystallizes in stellated groups 
of oblique rhomboidal prisms. These crystals are 
decomposed by a caustic alkali, to set free the 
aniline, and when this is distilled, water at first 
passes, then water charged with aniline, and lastly, 
at 359° F., chemically pure aniline. 



63 PREPARATION OF ANILINE. 



CHAPTER IX. 

ARTIFICIAL PREPARATION OF ANILINE— PREPARA- 
TION OF BENZOLE— PROPERTIES OF BENZOLE — 
PREPARATION OF N1TRO-BENZOLE — TRANSFOR- 
MATION OF NITRO-BENZOLE INTO AM LINE, BY 
MEANS OF SULPHIDE OF AMMONIUM j BY NASC! 
HYDROGEN; BY ACETATE OF IRON; AND BY 
ARSENITE OF POTASH — PROPERTIES OF THE BI- 
NITRO-BENZOLE. 

Artificial Preparation of Aniline. 

This process constitutes one of the most im- 
portant and curious reactions of organic chem- 
istry; it enables us to obtain aniline in any quan- 
tity. It is not difficult to prepare, but certain 
precautions are however necessary, when ope- 
rating on a large scale. The process can be 
subdivided into three distinct operations : — 

1. Preparation of benzole. 

2. Transformation of benzole into nitroben- 
zole. 

3. Reduction of nitro-benzole into aniline. 






PREPARATION OF BENZOLE. 69 

§ 1. Preparation of Benzole. 

The only process we think necessary to notice 
is that by which benzole is obtained on a large 
scale, viz : the extraction from coal tar, or from 
the first products of the distillation of coal tar, 
light oil, or crude naphtha. 

The manufacturer who wishes to distil tar in 
order to procure the largest amount of benzole, 
should choose a light fluid tar, and especially one 
distilled from boghead or cannel coal. To form a 
comparative estimate of the value of different tars, 
the following experiment may be performed: — 

About 2J gls. of tar are distilled until the 
vapors, instead of condensing into a liquid, fur- 
nish a product which, on cooling, becomes solid, 
or of a buttery consistence. By carefully observ- 
ing when the condensed oil becomes heavier than 
the water, and measuring the volume of the lighter 
oils which float on the surface of the water, and 
then comparing the volumes, we are enabled to 
estimate with tolerable accuracy the value of the 
tar. Of course, the one which yields the largest 
amount of light oil is the best. 

Crude naphtha, or the benzole of commerce, is 
generally a yellow or brown liquid, having a 
density varying from .90 to .95 ; it usually con- 
tains, besides benzole, some of the homologues of 
benzole, toluol, cumol, and cymol. It is impossi- 
ble to separate these bodies by an ordinary pro- 



70 PREPARATION OF BENZOLE. 

cess of rectification ; for although the boiling point 
of toluol is 226° or 228°, and that of cumol 289° 
or 293°, their vapors are, so to say, dissolved in 
the vapor of benzole, and are carried over and 
condensed together. Their presence, however, 
does not interfere with the preparation of nitro- 
benzole and aniline. 

When you have obtained the light oil from 
the coal tar, wash it with a little sulphuric acid 
(10 per cent, of strong acid). Leave it one hour, 
and saturate with soda. 

Distil ; the product escapes through a cool 
worm. 

In the receiver are two oils, one lighter and 
the other heavier than water, the first occupies 
about one-tenth of the total volume : it is the 
benzole; add to it a little sulphuric acid, wash 
and distil it. 

The benzole found in commerce is sometimes 
very impure; some has been met with, contain- 
ing merely a trace of real benzole. Such an 
article is ordinarily the result of the distillation 
of bituminous schists or asphaltum, and besides 
hydrocarbons belonging to another series than 
that of benzole, it generally contains a small 
amount of oxygenated products, and consequently 
cannot be advantageously used in the preparation 
of aniline. It is therefore important to be able 
to detect benzole in a mixture of other oils. For 
this purpose we may avail ourselves of the facility 



PROPERTIES OF BENZOLE. 71 

with which true benzole is converted into nitro- 
benzole, and then into aniline by the action of 
nascent hydrogen. 

The following is Hoffmann's method : a drop of 
benzole is heated in a small test tube, with fuming 
nitric acid, to convert it into nitro-benzole. A 
good deal of water is then added, to precipitate 
the nitro-benzole in small drops, which must be 
taken up by ether. The ethereal solution is 
then poured into another small tube, and equal 
volumes of alcohol and diluted hydrochloric acid 
are then added; a few fragments of granulated 
zinc are then dropped in. In about 5 minutes 
sufficient hydrogen will have been disengaged to 
produce aniline ; which will be found combined 
with the acid. The liquid is supersaturated with 
an alkali and shaken with ether, which dissolves 
the aniline set free. A drop of this ethereal solu- 
tion allowed to evaporate in a watch glass, and 
mixed after the evaporation of the ether with a 
drop of a solution of hypochlorite of lime, will 
show the violet tints which characterize aniline. 
The operations may be executed rapidly, ^and 
without any difficulty. 

Properties of Benzole. 

At the ordinary temperature, benzole is in the 
form of a colorless, very fluid liquid, of an agree- 
able odor, and has a specific gravity of .85 at 



72 PROPERTIES OF BENZOLE. 

59° F. At a very low temperature it crystallizes or 
forms a mass like camphor, which melts at 41°. 

Its boiling point is between 176° and 170°.8 ; 
and it distils without undergoing any change. It 
is nearly insoluble in water, to which it imparts 
its peculiar odor; it is very soluble in alcohol, 
ether, wood spirit, the essential and fatty oils ; it 
easily dissolves camphor, wax, fatty matters, India 
rubber, gutta percha, and a great number of resins. 
Amongst .the last those which are the least soluble 
in it are shellac, copal, and animi. It is very in- 
flammable, and burns with a smoky flame. Hy- 
drogen gas passed through it, and charged with 
its vapor, burns with a very clear, luminous flame. 

Chlorine and bromine convert benzole into the 
terchloride and terbromide of benzole. To the 
direct solar light, the change takes place very 
quickly. Concentrated sulphuric acid dissolves 
benzole, and when the mixture is gently heated a 
copulated acid, sidpho-bcnzoUc acid, is formed, C 12 , 
H 6 ,S 2 ,0 6 , the hydrogen of which may be replaced 
by metals. As this acid is soluble in water, in 
purifying rough benzole with sulphuric acid, it is 
necessary to avoid using an excess of the acid, 
and also heating the mixture. A solution of 
chromic acid does not act on benzole, and is there- 
fore a good agent for the purification. Concen- 
trated nitric acid converts benzole into nitro- 
benzole, to the manufacture of which we proceed. 



PREPARATION OF NITRO-BENZOLE. 73 

Preparation of Nitro-BenzoU. 

The preparation of nitro-benzole is accom- 
plished on a large scale, by allowing a fine stream 
of benzole, and another of the strongest nitric 
acid, to run together in a worm or long glass tube 
kept well cooled. The two liquids react on each 
other on coming in contact, heat is disengaged, 
and nitro-benzole is formed. 

Commercial nitric acid, mixed with half its 
volume of sulphuric acid, may be substituted for 
the concentrated nitric acid. 

The nitro-benzole collected at the end of the 
worm, is first washed with water, then with a 
solution of carbonate of soda, and afterwards once 
more with water. 

Properties of Nitro and Bi- Nitro- Benzole — 
Nitro- Benzole. 

Nitro-benzole is a yellowish liquid, which, at 
59° F., has a specific gravity of 1.209. It boils 
at 415°, 4 F., and cools at 37°, 4; it crystallizes in 
needles. Having an odor closely resembling that 
of the bitter almond, it'has been largely used in 
perfumery for scenting fancy soaps, for which 
purpose it has one advantage over the oil of bitter 
almonds— it is less affected by the action of alka- 
lies. Almost insoluble in water, it is very soluble 
in alcohol, ether, and essential oils. 

Concentrated sulphuric and nitric acids dissolve 
7 



74 BI-NITRO-BENZOLE. 

it, but it is precipitated by the addition of water. 
Tt is decomposed by a continued boiling with 
sulphuric acid; and under the same circumstances 
with concentrated nitric acid, it forms bi-nitro- 
benzole. Neither the alkalies in strong aqueous 
solution, nor quick lime, act on nitro-benzole; 
but an alcoholic solution of the alkalies, acts 
energetically and forms azoxy-benzole (C 24 ,H ,0 ,N 2 , 
O 2 ). By the action of nitric acid on this last 
substance a number of other interesting bodies are 
produced, which it is not necessary to describe 
here. 

Bi-Nttro-B 

Bi-nitro-benzole is formed when nitro-benzole 
is added, drop by drop, to a mixture of equal parts 
of fuming nitric acid and sulphuric acid, as long 
as the liquids will mix. If such a mixture be 
boiled for a few minutes, \l becomes, on cooling, 
a thick magma of bi-nitro-benzole, which is easily 
purified by "repeated washings with water. A 
single crystallization from alcohol will furnish 
this body in long brilliant prisms which melt at a 
temperature above 212°, -and crystallize again on 
cooling in a radiated mass. 

Bi-nitro-benzole is very soluble in warm alco- 
hol. When a plate of zinc, well cleaned, is placed 
in a cold alcoholic solution of bi-nitro-benzole, and 
hydrochloric acid is added by degrees, we observe 
that the disengagement of hydrogen, which at first 



BI-NITRO-BENZOLE. 75 

takes place, soon ceases, and at the same time the 
liquid takes a crimson red tint.* The reaction 
being completed, the excess of zinc is removed 
and the liquor is saturated by an alkali, which 
precipitates the oxide of zinc colored in deep pur- 
ple. The precipitate is collected on a filter and 
washed with alcohol. 

By distilling the highly colored alcoholic wash- 
ings, washing the residue with cold water, then 
re-dissolving it in alcohol and evaporating it afresh 
to dryness, the new matter is obtained perfectly 
pure. The authors have given it the name of 
Nitrosophenyline, C 12 H 6 N 2 O 2 . When obtained as 
above, it is a black shining substance; w r hen 
heated, it fuses and decomposes directly; it is 
almost insoluble in water, but freely soluble in 
alcohol and acids. An alcoholic solution contain- 
ing only 0.2 per cent, is so deeply colored that by 
reflected light the solution seems opaque and of 
an orange red. 

Concentrated hydrochloric and diluted sulphuric 
and nitric acids form magnificent crimson red solu- 
tions with nitrosophenyline, which is precipitated 
from them again unchanged by alkalies. 

Bi-nitro-benzole treated with an alcoholic solu- 
tion of sulphide of ammonium, is at first converted 
into nitro-aniline. 

C 12 H 6 (NO) 4 N=C 12 H 6 N 2 O 4 , 

* Church & Perkins. Quart. Journ. Chem. Soc, ix. p. 1. 



76 BI-NITRO-BENZOLE. 

that is to say, aniline, in which one equivalent of 
hydrogen is replaced by one of nitrous vapor. 
Nitro-aniline crystallizes in yellow needles, which 
stain the epidermis like picric acid. 

Transformation of Nitro- Benzole into Aniline. 

(a). By means of Sulphide of Ammonium. — An 
alcoholic solution of nitro-benzole, after having 
been saturated with ammoniacal gas, is treated 
with a current of sulphuretted hydrogen. The 
liquor now becomes of a deep dirty green color, 
and deposits a little sulphur. It is now left twenty- 
four hours, during which time crystals of sulphur 
are deposited, the odor of sulphuretted hydrogen 
disappears, and is replaced by a strong ammoniacal 
smell. If distilled now to recover the alcohol, a 
good deal of sulphur is deposited, and it is impos- 
sible to continue the distillation long, on account 
of the violent bumping which ensues. It is, there- 
fore, allowed to cool, and the sulphur is removed. 
On distilling the liquor again, more sulphur is 
deposited, which must also be removed. The 
process must be continued, re-saturating the liquor 
with sulphuretted hydrogen if need be, until a 
heavy oily matter (aniline) deposits, which must 
be separated from the liquor and re-distilled by 
itself. The aniline is thus obtained nearly pure. 

Instead of using an alcoholic solution of nitro- 
benzole, and treating it successively with ammonia 
and sulphuretted hydrogen, the alcoholic solution 



REDUCTION OF NITRO-BENZOLE. 77 

of sulphide of ammonium may be prepared before- 
hand, and the nitro-benzole poured into it. A 
part is dissolved immediately, and the remainder 
by dryness in the course of the operation. It is 
sometimes advantageous, instead of waiting until 
the aniline separates, to add hydrochloric acid to 
the liquor in the retort until it is slightly acid, 
and then to distil almost to dryness, by which 
means chloride of aniline is obtained. This is 
decomposed by an excess of caustic soda, and the 
aniline set at liberty, is distilled off. 

To avoid any danger from the bumping, a tinned 
copper still must be used, which should be heated 
by steam under a high pressure ; at first the tem- 
perature should not exceed 162° F., but after some 
time it could be raised to 212° or 230° F. 

The ammoniacal alcohol condensed in the worm 
may be re-saturated with sulphuretted hydrogen, 
and used over again with a new quantity of nitro- 
benzole. 

(b). Reduction of Nitro- Benzole by Nascent Hydro- 
gen. — In preparing aniline by this process, the 
nitro-benzole and zinc are placed in a vessel, and 
diluted hydrochloric or sulphuric acid is added 
so as to produce the disengagement of a small 
quantity of hydrogen. By degrees the nitro-ben- 
zole disappears, and aniline is formed, which re- 
mains in solution in hydrochloric or sulphuric 
acid. 



78 REDUCTION OF NITRO-BENZOLE. 

To isolate it, an excess of caustic soda is added 
and the mixture is distilled; the aniline passes over 
with the vapor of water. 

Beauchamp first recommended the employment 
of acetic acid and iron filings. He places in a re- 
tort 1 lb. of nitro-benzole, 1J lb. of iron filings, 1 
lb. of concentrated acetic acid. The reaction takes 
place without the application of external heat, the 
mixture becoming hot by itself, and the vapor 
being condensed in a receiver which must be kept 
well cooled. The condensed products consist of 
aniline, acetate of aniline, and some unchanged 
nitro-benzole. These are allowed to cool, and are 
then returned to the retort and again distilled to 
dryness. 

The distillate is now treated with fused caustic 
potash, and the aniline separates as an oily layer, 
which must be removed and distilled once more. 

The residue of the mixture of iron filings, acetic 
acid and nitro-benzole, which remains in the re- 
tort after the distillation, still contains a consider- 
able amount of aniline; to obtain this, the retort 
must be washed out with water acidulated with 
sulphuric or hydrochloric acid, and the solution 
filtered, and then evaporated to dryness. 

The dry residue is then mixed with quick lime 
and placed in an iron or refractory ware retort, 
and distilled, and the aniline thus pbtained must 
be rectified. 



REDUCTION OF NITKO- BENZOLE, ETC. 79 



(c). Reduction of Nitro-Benzole by Acetate of Iron. 
— Acetate of iron reacts on nitro-benzole and con- 
verts it into aniline, while the sulphate, chloride 
and oxalate of iron, have no action on it. The 
reaction is represented thus, 

C 12 H 5 AzO 4 + 12 FeO + 2HO + A= 

Nitro Benzole + Acetate of Iron, 

C 12 H 7 Az + A 



Aniline + Acetic Acid. 

One part of nitro-benzole is placed in a retort 
with an aqueous solution of acetate of iron, the 
retort is then heated over a water bath for several 
hours, and then the contents are filtered, being 
dilated with water if they have become pasty. 

The residue left on the filter, which is princi- 
pally peroxide of iron, is washed with boiling 
water. The filtrate and washings are then dis- 
tilled. The condensed products being water, 
acetic acid, and acetate of aniline. These may be 
again distilled with strong sulphuric acid, using 
4-10 the weight of the nitro-benzole employed to 
recover the acetic acid, and form sulphate of 
aniline, and the latter may be decomposed by 
caustic potash and the aniline distilled off. This 
process has not been found advantageous, and has 
consequently been given up. 



80 REDUCTION OF NITRO-BENZOLE, ETC. 

(d). Reduction of Nitro- Benzole by Means of Arse- 
nite of Potash or Soda. — In this process digest 
nitro-benzole with a solution of arsenious acid in 
a strong lye of caustic soda or potash, or place the 
arsenical solution in a tubulated retort, heat it to 
the boiling point, and then allow the nitro-benzole 
to fall drop by drop in it. Under these circum- 
stances, nitro-benzole is transformed into aniline, 
which distils over, and it is only necessary to 
saturate with an alcoholic solution of oxalic acid 
to obtain perfectly pure oxalate of aniline. 






ANILINE PURPLE. 81 



CHAPTER X. 

ANILINE PURPLE — YIOLINE — ROSEINE — EMERAL- 
DINE — BLEU DE PARIS. 

§ 1. Aniline Purple. 

It has been known &r many years that hypo- 
chlorites react on aniline and its salts, producing 
a purple-colored solution; in fact, hypochlorites 
are the distinguishing test for aniline ; but nothing 
definite was known of this purple-colored solu- 
tion, it being simply stated that aniline produced 
with hypochlorites a purple-colored liquid, but 
that this color was very fugitive. Many absurd 
statements have been made respecting the dis- 
covery of aniline purple. We will just briefly 
mention how it was discovered by Mr. Perkins. 

In the early part of 1856, he commenced an 
investigation on the artificial formation of quinia. 
To obtain this basis, he proposes to act on tolui- 
dine with iodide of allyle, so as to form allyle 
toluidine, which has the formula : — 



N = C 10 , H 13 , N. 










82 ANILINE PURPLE. 

thinking it not improbable that by oxidizing 
this, he might obtain tire desired result thus: — 
2 (C 10 H 13 N) + O 3 - C 20 II 24 N 2 O 2 +H 2 O. 

Allyle-toluidine. Quinia. 

For this purpose he mixed the neutral sulphate 
of allyle toluidine with bichromate of potash ; but 
instead of quinia he obtained a dirty reddish- 
brown precipitate. Nevertheless, being anxious 
to know more about this curious reaction, he pro- 
ceeded to examine a more simple base under the 
same circumstances. For this purpose he selected 
aniline, and treated its sulphate with bichromate 
of potash. This mixture produced nothing but a 
very unpromising black precipitate, but on in- 
vestigating this precipitate he found it to contain 
the substance which is now, we may say, a com- 
mercial necessity, namely, aniline purple. 

The method adopted for the preparation of 
aniline purple is as follows: Solutions of equiva- 
lent proportions of sulphate of aniline and bi- 
chromate of potash are mixed, and allowed to 
stand till the reaction is complete. The resulting 
black precipitate is then thrown on a filter, and 
washed with water until free from sulphate of 
potash. It is then dried. This dry product is 
afterwards digested several times with coal-tar 
naphtha until all resinous matter is separated, 
and the naphtha ceases to be colored brown. 
After this it is repeatedly boiled with alcohol to 



ANILINE PURPLE. 83 

extract the coloring matter. This. alcoholic solu- 
tion, when distilled, leaves the coloring matter in 
the bottom of the retort as a beautiful bronze- 
colored substance. 

The aniline purple prepared according to the 
process just described, although suitable for prac- 
tical purposes, is not chemically pure. If re- 
quired pure, it is best to boil it in a large quan- 
tity of water, then filter the resulting colored 
solution, and precipitate the coloring matter from 
it by means of an alkali. The precipitate thus 
obtained should be collected on a filter, washed 
with water until free from alkali, and driei 
When dry it is to be dissolved in absolute alcohol, 
the resulting solution filtered, and then evapo- 
rated to dryness over the water-bath. Thus 
obtained, aniline purple appears as a brittle sub- 
stance, having a beautiful bronze-colored surface; 
but if some of its alcoholic solution be evaporated 
on a glass plate, and viewed by transmitted light, 
it appears a beautiful bluish violet color. If 
considerable quantities of an alcoholic solution of 
the coloring matter, containing a little water, be 
evaporated to dryness, the surface of the coloring 
matter next to the evaporating dish when detached, 
often possesses a golden green appearance. Ani- 
line purple is, with difficulty, soluble in cold 
water, although it imparts a deep purple color to 
that liquid. It is more soluble in hot water, but 
its hot aqueous solution when left to cool t assumes 



84 ANILINE PURPLE. 

the form of a purple jelly. It is very soluble in 
alcohol, though nearly insoluble in • ether and 
hydrocarbons. Aniline dissolves it readily. In 
properties, it seems to be slightly basic, as it is 
more soluble in acidulated than in pure water. 
Alkalies and saline substances precipitate it from 
its aqueous solution, as a dark purplish-black 
powder. Bichloride of mercury precipitates it 
in a very finely divided state; a little of this pre- 
cipitate, which appears to be a double compound 
of chloride of mercury and coloring matter, when 
suspended in water and viewed by transmitted 
light, appears of a blue or violet color. If a small 
quantity of hydrates of potash or soda be added to 
an alcoholic solution of the coloring matter, it 
causes it to assume a violet tint, but without 
effecting any change in the coloring matter itself. 
Ebullition with alcoholic potash does not decom- 
pose it. Aniline purple dissolves in concent); 
sulphuric acid, forming a dirty green solution. 
This, when slightly diluted, assumes a beautiful 
blue color. Excess of water restores it to its 
original purple color. We have had a specimen 
of this coloring matter heated for an hour to 100° 
Centigrade with Nordhausen sulphuric acid, with- 
out suffering decomposition, being restored to its 
original color by means of water, and possessing 
precisely the same properties as it had before 
being subjected to this powerful agent. Hydro- 
chloric acid acts upon it in the same manner as 



ANILINE PURPLE. 85 

sulphuric acid. It is decomposed by chlorine, 
and also by fuming nitric acid. Bichloride of tin 
is without action upon it. Powerful reducing 
agents have a peculiar action upon this coloring 
matter, somewhat analogous to the action of re- 
ducing agents on indigo. An alcoholic solution 
of the coloring matter when mixed with a little 
protoxide of iron changes to a pale brown color. 
This solution also becomes purple when exposed 
to the action of the atmosphere. Sulphurous 
acid does not affect the color of this substance. 

This coloring matter forms a remarkable com- 
pound with tannin. When an aqueous solution 
of the coloring matter is mixed with a solution of 
tannin, precipitation takes place ; the precipitate 
thus formed, after having been well washed, no 
longer possesses the properties of the pure color- 
ing matter. It is insoluble in water. Like the 
pure coloring matter, it dissolves in concentrated 
sulphuric acid, forming a dirty green liquid, but 
on adding an excess of water to that solution, the 
new compound is precipitated unchanged. This 
compound is rather duller in color than the pure 
coloring matter itself. Aniline purple, when 
agitated with a little moist binoxide of lead, is 
transformed into Eoseine. Its coloring matter is 
remarkable for its intensity ; a few grains will 
color a considerable quantity of' spirit of wine. 



8 






86 VIOLINE. 

§ 2. Violine. 

This coloring matter, which is a product of the 
oxidation of aniline, was first obtained by Dr. 
David Price. He prepares it by heating an aqueous 
liquid, containing two equivalents of sulphuric 
acid and one equivalent of aniline, to the boiling 
point, and then adding one equivalent of binoxide 
of lead, boiling the mixture for some time and 
filtering it whilst hot. The filtrate, which is of a 
dark purple hue, is boiled with potash, to separate 
the excess of aniline, and also to precipitate the 
coloring matter. When all the free aniline is 
volatilized, the residue is thrown on a filter and 
slightly washed with water, and then dissolved in 
a dilute solution of tartaric acid. This solution, 
after filtration, is evaporated to a small bulk, re- 
filtered, and then precipitated by means of an 
alkali. Thus obtained, violine presents itself as a 
blackish purple powder, which, when dissolved in 
alcohol and evaporated to dryness, appears as a 
brittle, bronze-colored substance, similar to aniline 
purple, but possessing a more coppery colored 
reflection. It is more insoluble in water than the 
preceding coloring matter; it is very soluble in 
alcohol ; insoluble in ether and hydrocarbons : 
these solutions possess a color somewhat similar 
to that of the field violet. Concentrated sulphuric 
acid dissolves it, forming a green solution, but 
excess of water restores it to its original color. 



ROSEINE. 37 

Like aniline purple, reducing agents deprive it 
of its color, which is restored by the action of the 
atmosphere. Tannin produces an insoluble com- 
pound with it. When agitated with a small 
quantity of binoxide of lead, it is converted into 
aniline purple, excess of this reagent changes it 
into roseine. 

§ 3. Roseine. 

This substance nearly always accompanies ani- 
line purple, though, in very small quantities. It 
was first noticed publicly by C. Greville Williams, 
and afterwards by Dr. David Price. Williams 
used manganates for its preparation, but Dr. David 
Price prepared it by mgans of binoxide of lead. 
His process is as follows : To a boiling solution of 
one equivalent of sulphate of aniline, two equiva- 
lents of binoxide of lead are added, and the 
mixture boiled for a short time. The rose-colored 
solution is then filtered, and the filtrate evaporated 
to small bulk, which causes a certain amount of 
resinous matter to be separated; this evaporated 
solution is then filtered, and the coloring matter 
precipitated by means of an alkali, it is then col- 
lected on a filter, slightly washed, and then dried. 
The coloring matter thus prepared, readily dis- 
solves in alcohol, forming a fine crimson colored 
liquid, which when evaporated to dryness, leaves 
the coloring matter as a dark brittle substance, 
having a slightly metallic reflection. It is much 



88 EMERALDINE, OR ANILINE GREEN. 

more soluble in water than either aniline purple 
or violine, but like them it is insoluble in hydro- 
carbons, and is more soluble in acids than in 
neutral liquids. Concentrated sulphuric acid dis- 
solves it, forming a green solution ; excess of 
water restores it to its original color. It forms a 
compound with tannin ; and is also decolorized, or 
nearly so, by powerful reducing agents. 

The three coloring matters just mentioned, 
namely, aniline jpurple, violine and roseine, arc 
evidently closely allied, for they have nearly the 
same properties. They are all formed under simi- 
lar circumstances, namely, by the action of oxidiz- 
ing agents in the presence of water; they are all 
slightly soluble in water, though as the shade of 
color becomes redder, so their solubility increases; 
alkalies precipitate them from their aqueous solu- 
tions; concentrated sulphuric acid dissolves their^ 
forming green solutions which an excess of water 
restores to the original color of the coloring mat- 
ters ; powerful reducing agents deprive them of 
their color or nearly so, but it is again restored by 
the influence of oxygen ; and lastly, tannin forms 
insoluble compounds with them all. 

§ 4. Emeraldine or Aniline Green. 

Most chemists, who have worked with aniline 
in the laboratory, must have noticed the peculiar 
green-colored substance which forms on the out- 
side of the various kinds of chemical apparatus 



BLEU DE PARIS. 89 

that have been standing in the vicinity of any 
quantity of this body. This product is aniline 
green. It has been known for several years; it 
may be formed by various processes. One consists 
in oxidizing aniline with chloric acid; this is 
effected by mixing an hydrochloric solution of 
aniline with chlorate of potash. It may also be 
obtained by oxidizing a salt of aniline by perchlo- 
ride of iron. Obtained by either of these processes, 
it presents itself as a dull green precipitate, which 
when dried assumes an olive green color. It is 
insoluble in water, alcohol, ether and benzole. 
Sulphuric acid dissolves it, forming a dirty purple- 
colored solution, from which it is precipitated 
unchanged by water. With alkaline solutions, 
it changes to a deep color somewhat similar to 
indigo, but acids restore it to its original color. 
The color of aniline green is much enlivened by 
the presence of an excess of acid, but unfortunately 
as soon as this acid is removed, it passes back t*> 
its normal color. 

§ 5. Bleu de Paris. 

This is another 'coloring matter produced under 
circumstances similar to those which give Fut- 
schine. MM. Persoz, De Luynes, and Salvetat 
give the following account of its preparation and 
properties: "9 grains of bichloride of tin and 
16 grains of aniline heated for thirty hours at a 

8* 



90 BLEU DE PARIS. 

temperature of about 356° F., in a sealed tube ? 
produce neither a red nor a violet, but a very pure 
and lively blue." Mr. Perkins repeated the ex- 
periment twice, but he obtained only a dirty green 
color ; but at last he obtained the blue as described 
by MM. Persoz, De Luynes, and Salvetat. This 
blue crystallizes from the alcoholic solution in the 
form of fine needles, having the aspect of ammo- 
niacal sulphate of copper; soluble in water, alco- 
hol, wood-spirit and acetic acid ; insoluble in ether 
and bisulphide of carbon. With concentrated 
sulphuric acid it forms an amber-colored solution, 
which water converts into a magnificent blue li- 
quid. Strong nitric acid decomposes it, chromic 
acid precipitates it from its aqueous solution with- 
out decomposition, chlorine destroys it, sulphurous 

* When you break the tubes in which the reaction has 
been effected, you obtain a blackish matter which, exhausted 
bv boiling water, colors it blue; the solution, treated by 
common salt, left to precipitate the coloring matter that 
you collect on a filter, whilst the liquor takes a green shade 
more or less dark. The blue precipitate I Lved anew 

in water, and precipitated again by the chloride of sodium. 
This operation is repeated several times to separate i 
pletely the green coloring matter, at last precipitate by few 
drops of hydrochloric acid, collect the blue matter on a filter, 
wash first with water acidulated with hydrochloric acid, 
then with pure water, the washing is terminated when the 
water begins to pass blue. 

To obtain it crystallized, dissolve it in boiling alcohol, 
which, by cooling, deposits it in form of fine needl« 



BLEU DE PARIS. 91 

acid does not decolorize it, sulphide of ammonium 
is without action upon it. It is precipitated from 
its aqueous solution by alkalies and saline com- 
pounds. Submitted to the action of heat, it melts 
and decomposes in giving violet vapors. 



92 FUTSCHINE, OR MAGENTA. 



CHAPTER XL 

FUTSCHINE, OR MAGENTA. 

This beautiful product, which is often impro- 
perly called Roseine, is a member of an entirely 
different series of compounds from the foregoing, 
being formed under very different circumstances, 
and possessing very different properties. This 
coloring matter was first observed by Natanson, 
in 1856, when studying the action of chloride of 
Ethylene on aniline, and afterwards, shortly before 
it was practically introduced into the arts, by Dr. 
Hoffmann, when preparing cyantrephenile-diamine 
by the action of bichloride of carbon on aniline. 
It was M. Verguin who first brought it forward 
as a dyeing agent, and who, we believe, taught 
manufacturers how to prepare it on a large scale. 
Futschine is invariably formed at a temperature 
ranging from 17° to 19° Centigrade. It is pro- 
duced from aniline by the action of reducible 
chloronized, brominized, iodized or fluorized sub- 
stances, as well as by weak oxidizing agents. 
The substances used for its preparation on the 
large scale are perchlorides of tin and of mercury, 



FUTSCHINE, OR MAGENTA. 93 

and the nitrate of mercury. It has also been pre- 
pared with bichloride of carbon. * . 

Preparation of Futschine by the action of Bichlo- 
ride of Tin on Aniline. — Aniline combines with bi- 
chloride of tin, evidently producing a double com- 
pound. This product is a white substance, and 
may be prepared by adding to aniline, bichloride 
of tin in the anhydrous state or dissolved in water. 
Anhydrous bichloride of tin combines with aniline 
with great energy to form this compound. To 
prepare Futschine from the double compound, it is 
necessary that it should be free from water, or 
nearly so ; therefore anhydrous bichloride of tin is 
generally employed for its preparation. The pro- 
cess adopted is as follows : anhydrous bichloride 
of tin is slowly added to an excess of aniline, the 
mixture being constantly stirred, and the pasty 
mass thus formed gradually heated; as the tem- 
perature increases, it becomes quite liquid and 
also brown in color. As soon as the temperature 
nearly approaches the boiling point, the mixture 
rapidly changes to a black-looking liquid, which, 
when viewed in thin layers, presents a rich crim- 
son color; this is kept at its boiling point some 
time, and then well boiled with a large quantity 
of water ; by this means the principal part of the 
coloring matter is extracted, together with con- 
siderable quantities of tin in the form of a proto- 
compound. The aqueous solution of the coloring 
matter and hydrochlorate of aniline is then boiled, 



94 FUTSCHINE, OR MAGENTA. 

so as to volatilize any free aniline it may contain, 
and then saturated with chloride of sodium. The 
chloride of sodium causes the coloring matter to 
separate as a semi-solid, pitchy substance of a 
golden green aspect, while the hydrochlorate of 
aniline remains in solution. The coloring matter 
thus obtained, may be further purified by di- 
gestion with benzole, which dissolves out a cer- 
tain amount of resinous matter. 

Preparation of Futschine by the Action of Nitrate 
of Mercury on Aniline. — When protonitrate of 
mercury is left in contact with aniline for some 
time, it forms a white pasty mass, but when care- 
fully heated to 170° or 180° Centigrade, it reacts 
upon it, forming a brown liquid, which gradually 
changes till of a dark crimson color. At the 
same time the whole of the metal of the mercury 
salt collects at the bottom of the vessel the expe- 
riment is conducted in. This product, when 
separated from the metallic mercury and allowed 
to cool, becomes semi-solid, being filled with 
crystals of nitrate of aniline. To purify this pro- 
duct it is best to dissolve out the nitrate of aniline 
it contains, in a small quantity of cold water, and 
then to boil the regaining product several times 
with fresh quantities of water, until the principal 
of the coloring matter is extracted, and filter the 
resulting aqueous solution while hot. On cool- 
ing, the solution will deposit the coloring matter 
as a golden-green, tarry substance, from which 



FUTSCHINE, OR MAGENTA. 95 

benzole separates a small quantity of a brown 
impurity, leaving the coloring matter as a brittle 
solid. 

We have briefly described the above processes, 
because they may, to some extent, be regarded as 
types of most of the methods employed for the 
production of this coloring matter; the first, re- 
presenting its formation, by the action of reduc- 
ible chlorides upon aniline, and the latter by the 
influence of weak oxidizing agents. 

Futschine is undoubtedly an organic basis, and 
a more powerful one than is generally supposed. 
The products obtained from aniline by means of 
bichloride of tin, is hydrochlorate of Futschine, 
and that obtained by the oxidizing action of ni- 
trate of mercury, is the nitrate of Futschine. Our 
reason for stating this is, that on examining the 
coloring matter obtained by chloride of tin, it is 
found to contain large quantities of combined hy- 
drochloric acid, and when nitrate of mercury was 
used, considerable quantities of combined nitric 
acid, therefore we conclude that the former is the 
hydrochlorate and the latter the nitrate. 

Futschine is separated from its salts by precipi- 
tation with a small quantity of ammonia. When 
freshly precipitated, Futschine is a red, bulky 
paste, which, when dry, contracts, forming a 
purplish red powder. It is difficultly soluble in 
water, but an excess either of hydrochloric or sul- 
phuric acid dissolves it, forming a brownish yellow 



06 FUTSCHINE, OK MAGENTA. 

liquid, from which ammonia separates it un-. 
changed. By this reaction it may be distinguished 
from Boseine, which dissolves in strong sulphuric 
acid producing a green liquid. Caustic alkalies 
or ammonia in excess partially precipitate Futschine 
from its salts, but at the same time dissolve a con- 
siderable quantity of it, forming nearly colorless 
liquids. Acetic acid added to these alkaline solu- 
tions, restores the color of the Futschine; and if 
the liquids are concentrated, the bases precipitate 
it as a red, flocculcnt substance. An alcoholic 
solution of Futschine, when evaporated to dryi 
leaves the coloring matter as a brittle mass, having 
a beautiful golden-green metallic reflection. By 
transmitted light it has a red color. Futschine 
has been analyzed, and is represented by the for- 
mula, C ,2 II 12 N 2 0. 

In the hydrochlorate, Mr. Bechamp found a 
quantity of hydrochloric acid corresponding with 
the formula C 12 II ,2 N 2 1IC1. lie also examined 
the hydrochloro-platinatc which is a purple pre- 
cipitate; it has the formula C I2 ]I ,2 N°( HIT: 
The existence of oxygen in this basis is remark- 
able, because, in many instances, it is produced 
from agents which do not contain a trace of oxy- 
gen, as, for example, bichloride of tin and aniline. 
The only way to account for the presence of oxy- 
gen in the product analyzed, is as an hydrate, 
thus : — 



FUTSCHINE, OR MAGENTA. 97 

C 12 H ,2 N 2 m C ,2 H ,0 N 2 + H 2 

Futschine. Anhydrous Water. 

Futschine. 

This is, perhaps, to some extent confirmed by 
an experiment made with iodaniline. Iodaniline, 
when heated, yields Futschine; this change can be 
expressed thus : — 

2 (C 6 [H 6 1] N) = C 12 H 10 N 2 + 2HI 

Iodaniline. Anhydrous Iodhydric 

Futschine. Acid. 

But supposing the Futschine examined by Mr. 
Bechamp to have been -an hydrate, it is remark- 
able that its hydrochlorate, and, more particularly 
its hydrochloroplatinate should also be hydrates; 
but as our knowledge of this body is as yet but 
scanty, we must wait for the accumulation of 
facts before we can form any fixed opinion respect- 
ing its constitution. The compounds investigated 
by Mr. Bechamp appear to be uncrystallizable. 
Reducing agents decolorize Futschine, but the 
oxygen of the air renders it its color. Like 
aniline purple, Futschine is a very intense color- 
ing matter; tannin precipitates both Futschine 
and its salts, forming difficultly soluble substances. 
Bichloride of mercury precipitates this substance 
and its salts, forming double compounds ; when 
preparing Futschine by means of bichloride of 
tin, there are two coloring matters produced, one 
possessing an orange color, and the other a purple 
hue. Little is known of them, 
9 



98 COLORING MATTERS 



L 



CHAPTEE XII. 

COLORING MATTERS OBTAINED BY OTHER BASES 
FROM COAL TAR — NITROSO-PIIENYLINE — DI-XT- 
TRO-ANILINE — XITRO-PHEXYLINE — PICRIC ACID 
— ROSOLIC ACID — QUINOLIX v E. 

The bases toluidinc, xylidine, and cumidine, 
yield coloring matters under the oxidizing agents, 
and also when submitted to the aetion of reduci- 
ble chlorides, at high temperatures, analogous to 
those obtained from aniline under similar circum- 
stances, but the results generally are not so good, 
the color of the products becoming tinged with 
brown, as the bases get higher in the series. 

Nitroso-Plc 

This remarkable body is obtained by the action 
of nascent hydrogen on an alcoholic solution of 
di-nitro-benzole. It is represented by the formula 
C 6 H 6 N 2 0. This body is almost insoluble in water, 
but soluble in acids and in alcohol, producing 
crimson-colored solutions, but its color is not 
nearly so brilliant as that of Futschine. Any 
experiments with it, as regards its dyeing proper- 
ties, have not been tried 



OBTAINED FROM COAL TAR. 99 

Di-nitro- Aniline. 

Di-nitro-aniline is obtained by decomposing 
di-nitro-phenyle citra-conamide by means of car- 
bonate of soda. When pure, it crystallizes in 
yellow tables. It dissolves very sparingly in 
water, producing a yellow liquid. It has the 
formula C 6 H 5 (N0 2 )N 2 . It does not combine 
with acids or alkalies, although it appears to be 
more soluble in acidulated than in pure water. 
Silk can be dyed yellow with di-nitro-aniline. 

Nitro-phenylene diamine, or Nitro-azo-phenylamine. 

Di-nitro-aniline, when submitted to the action 
of sulphide of ammonium, changes into this beau- 
tiful base, which crystallizes in needles of a red 
color, somewhat similar in appearance to chromic 
acid. It dissolves in water, forming a yellow or 
orange-colored solution like that of bichromate 
of potash. Alcohol and ether dissolve it freely. 
This base possesses the power of dyeing silk a 
very clear golden color. 

Picric^ or Dinilro-phenic Acid. 

This beautiful acid was discovered as early as 
1788, by Hausmann. It may be obtained by the 
action of heated nitric acid on a great variety of 
substances. The following are the names of some 
of them : Indigo, Aniline, Carbolic acid, Saligenine, 
Salicylious and Salicylic acids, Salicin, Phlorizin, 



100 COLORING MATTERS 

Cumanin, Silk, Aloes, and various Gum-resins. It 
is now prepared for commercial purposes from 
carbolic acid, and also from certain gum-resins. 
We have prepared it from carbolic acid on a large 
scale, in the following manner, with success: As 
strong nitric acid acts very violently, when brought 
in contact with carbolic acid, we have found it 
best to use an acid having a gravity less than 1.:'1, 
so as partially to convert the carbolic acid, and 
afterwards to boil it in stronger acid to change it 
into picric acid. On diluting the acid solution, the 
impure picric acid precipitates; to further purify 
this, it should be crystallized from boiling w; 
When preparing this product for commercial pur- 
poses, it is advantageous to let all the nitrous fill 
formed in its preparation, together with a certain 
amount of atmospheric air, to pass over a fresh 
quantity of carbolic acid. This will absorb them 
and at the same time be converted into nitro, or 
di-nitro-phenic acid, and consequently diminish the 
quantity of nitric acid required for its manufac- 
ture. 

AVhcn preparing picric acid from carbolic acid, 
there is always a quantity of a yellow, r< mat- 

ter produced, and at times a considerable quantity 
of oxalic acid. The latter is always produced when 
the acid which is used to finally convert the car- 
bolic acid is too weak, for then it rapidly decom- 
poses the picric acid, yielding carbonic and oxalic 
acids. Picric acid, when pure and dry, is of a light 



OBTAINED FROM COAL TAR. 101 

primrose-yellow color ; crystallizing in strongly- 
shining lamina. It possesses an extremely bitter 
taste, and dissolves in water with a beautiful yellow 
color. When digested with protoxide of iron, in the 
cold, it yields a brown amorphous compound, which 
dissolves in water with a blood red color. Picric 
acid was introduced as a dye about five or six 
years since, by MM. Guinon, Marnas, and Bonney, 
eminent silk dyers of Lyons. Many of the cheap 
products sold as picric acid are of a brown color, 
and consist of impure di- and tri-nitro-phenic acids 
and sometimes of this crude product and ground 
turmeric. 

Rosolicacid. — Eunge first noticed this substance 
in 1834, when studying creosote, but it was almost 
lost sight of, until again observed by Dr. Hugo 
Miller only a short time since. He accidentally 
observed that when crude phenate of lime is ex- 
posed to a moist, heated atmosphere, as that of an 
ordinary drying stove, it gradually changes in 
color, and assumes a dark red tint; this coloration 
is owing to the formation of rosolate of lime. Dr. 
Muller prepared rosolic acid from this product in 
the following manner : The crude rosolate of lime 
is first boiled with a solution of carbonate of am- 
monia. By this means a crimson solution containing 
the rosolic acid is obtained ; this solution is then 
evaporated nearly to dryness, during such process 
ammonia is given off, and the crimson-colored 
liquid gradually changes to a yellowish red, and 

9* 



102 COLORING MATTER 

at the same time a dark resinous matter separates ; 
the resinous substance is crude rosolic acid. In 
order to purify it, it is submitted to the following 
treatment, proposed by Eunge: The crude rosolic 
acid is dissolved in alcohol, and by hydrate of 
lime in slight excess. The beautiful crimson 
solution which is thus formed is agitated for some 
time with the undissolved portion of the lime, 
filtered, and the filtrate diluted with water, and, 
lastly, the alcohol distilled off. The residuary 
rosolate of lime is then decomposed with just a 
sufficient quantity of acetic acid, and the whole 
boiled until every trace of free acetic acid and still 
adhering alcohol is volatilized. The rosolic acid 
separates first as a red precipitate, but when heated, 
cakes together, forming a dark, brittle substance, 
having a greenish metallic lustre. 

It may be still further purified by solution in 
alcohol, to which a little hydrochloric acid has 
been added, and precipitation with water. Pure 
rosolic acid is a dark amorphous substance, pos- 
sessing the greenish metallic lustre of cantharides. 
Its powder is of a red, or rather scarlet shade, 
which, if rubbed with a hard, smooth body, assumes 
a bright gold-like lustre. In thin layers, rosolic 
acid presents an orange color, when viewed with 
transmitted light, but with reflected light, a golden 
metallic appearance. When thrown down from an 
alcoholic solution with water, it forms a flocculent 
precipitate of a bright red color, resembling the 



OBTAINED FROM COAL TAR. 103 

basic chromate of lead. Concentrated acids, as 
acetic, hydrochloric, and sulphuric, dissolve rosolic 
acid, forming a brownish yellow solution, of which 
water precipitates rosolic acid unchanged. To cold 
water, it imparts a bright yellow color, and is 
more soluble in hot than cold water. Alcohol 
and ether dissolve it. With ammonia, caustic 
alkalies and caustic earths, it forms dark red com- 
pounds. These compounds are very unstable. No 
precipitates are formed with aqueous solutions of 
the rosolates, with the basic acetate of lead, or with 
any other metallic salt. According to Dr. Muller, 
it is represented by the formula C 23 H 22 4 . Eo- 
solic acid has been prepared lately on a large scale 
for the purpose of printing muslin. It was rosolate 
of magnesia which was employed. It is not used 
since the discovery of Futschine. 



104 NAPHTHALINE COLORS. 



CHAPTER XIII. 

NAPHTHALINE COLORS — CHLOROXYNAPHTIIALIC 
AND PERCnLOROXYNAPHTIIALIC ACIDS — CARMI- 
NAPHTHA — NIXAPHTIIALAMIXE — NITROSO- 
NAPHTIIALINE — NAPIITIIAMEIN — TAR RED — 
AZULIXE. 

The beautiful hydro-carbon naphthaline, which 
has yielded such a long category of substances to 
the chemist, up to the present time has yielded 
nothing of practical importance to the dyer. From 
it, the following color derivatives having been ob- 
tained, namely: Chloroxynaphthalicacid,Perchlor- 
oxynaphthalic acid, Carminaphtha, Ninaphthala- 
mine, Nitrosonaphthaline and Naphthamein. 

Chhroxijnaplitkalic and Pcrcltloroxynaplitlialic 
Acids. 

These acids were discovered by Laurent. They 
are produced by digesting the chlorides, namely: 
the chloride of chloroxynaphthyle and the chlo- 
ride of perchloroxynaphthyle with an alcoholic 
solution of hydrate of potash. They are difficult 
to obtain in quantity. Mr. Perkins has not ob- 
tained satisfactory results in their preparation. 
They have the formula C ,c (IP CI) O 3 and C l0 (II CI 5 ) 



NAPHTHALINE COLORS. 105 

O 3 respectively. They are regarded with great 
interest, as being very closely allied with alizarine, 
the coloring matter of madder; in fact they are 
viewed as chlor-alizaric acid. The synopsis is based 
upon the idea of alizarine having the formula C :0 
H 6 O 3 , but it happens very unfortunately for this 
theory, that the formula of alizarine itself is still a 
disputed point. Chloroxynaphthalic acid is of a 
yellow color, insoluble in water and with difficul- 
ty soluble in alcohol and ether ; it dissolves in 
concentrated sulphuric acid. This acid is a very 
sensible test for alkalies, being changed to an 
orange red by them. This may be shown by 
moistening paper with a weak alcoholic solution 
of this acid, drying it, and then exposing it to 
ammoniacal vapors. This will cause it to assume 
a red color. 

The chloroxynaphthalates are described as pos- 
sessing great beauty, and are of yellow, orange, 
or crimson colors. The potash salt is of a red 
crimson color, and slightly soluble in water ; the 
baryta salt crystallizes in sMky needles, having a 
golden reflection. The strontia, lime, alumina, 
and lead salts are of an orange color ; the cadmium 
salt is a vermilion colored precipitate ; the copper 
and cobalt salts are crimson ; and the mercury salt 
is of a red brown color. Once some silk was 
dyed with a small quantity of chloroxynaphthalate 
of ammonia, which Mr. Perkins prepared, and 
found it to produce a good golden yellow color, 



106 NAPHTHALINE COLORS. 

of great stabilty under the influence of light. 
Perchloroxynaphthalic acid is a yellow, crystalline 
body, insoluble in water, but soluble in alcohol 
and ether. With potash or ammonia it forms 
insoluble salts of red or crimson color of great 
beauty. 

Carminaphtha. 

This coloring matter was also discovered by 
Laurent. It is obtained by heating naphthaline 
with a solution of bichromate of potash, and then 
adding sulphuric or hydrochloric acids. It is 
described as a fine red substance, soluble in alka- 
lies, but precipitated from its alkaline Bolati 
by means of acids. Mr. Perkins never obtained 
this product when oxidizing naphthaline. 

Ninaphthdlamine, 

Ninaphthalamine is a name which has been 
given to a remarkable base which was noticed by 
Laurent and Zinin ; but nothing was known of its 
nature until rcsubjected to investigation by Mr, 
Wood, who has botli described and analyzed it 
and some salts. Its formula is C 10 (II 8 NO) N, or 
naphthalamine in which II is replaced by NO. 
Mr. Wood prepares this base in the following 
manner: Sulphuretted hydrogen is to be passed 
through a boiling solution of dinitronaphthaline 
in weak alcoholic ammonia, until nearly all the 
alcohol has distilled off, which operation should 
occupy two or three hours. The residue is then 



NAPHTHALINE C0L0KS. 107 

to be boiled with dilate sulphuric acid, and filtered. 
The filtrate, on cooling, deposits an impure sul- 
phate of ninaphthalamine in the form of brownish 
crystals which are purified by recrystallization in 
water two or three times. Mr. Perkins has found 
when crystallizing this salt, that it is best to use 
water acidulated with sulphuric acid. When pure, 
this sulphate has to be decomposed with ammonia, 
and the resulting precipitate of ninaphthalamine 
washed with water. Thus obtained, ninaphthala- 
mine appears as a bright red-colored crystalline 
precipitate, which, when viewed under a lens 
appears as beautiful needles. It is very soluble 
in alcohol, producing a solution which, when diluted, 
is of an orange color slightly tinged with brown, 
not nearly so pure in color as that of nitropheny- 
linediamine. It is slightly soluble in water, and 
possesses* the power of dyeing silk with a color 
somewhat similar to that of ordinary annoto. 
With acids it produces colorless salts. Its formula 
is the same as that of nitroso-naphthaline, though 
it possesses very different properties. As a dyeing 
agent we do not think it would be of any value 
even if it could be obtained cheaply. 

Nitroso-naphthaline. 

m 

This peculiar body is a product of the action 
of nitrous acid on naphthalamine. . It is prepared 
by mixing a solution of hydrochlorate of naphtha- 
lamine with nitrate of potash. From this mixture 



108 NAPHTHALINE COLORS. 

it separates a reddish brown precipitate. This, 
when washed with water on a filter and then dried, 
is dissolved in alcohol, filtered, and evaporated to 
dryness on the water-bath. Thus prepared, it is 
a crystalline, dark-colored substance, having a 
greenish metallic reflection. It is soluble in al- 
cohol, and also in benzole, forming orange red 
solutions. When acids are added to an alcoholic 
solution of nitroso-naphthalinc it immediately 
assumes a most beautiful violet color, as fine as 
aniline purple. Alkalies restore it to its original 
color. Silk may be dyed a beautiful purple sha<le 
with this substance, provided a certain quantity 
of hydrochloric or sulphuric acids be present. But 
what is most unfortunate is, that when the silk 
thus dyed is rinsed in water, the color immediately 
passes back to that of the pure nitroso-naphthalinc, 
and also that the amount of acid require'd to k 
up the purple shade if left in the silk rots it in a 
few days. Could this purple be fixed, nitroso- 
naphthaline would be a cheap and most useful 
dye. Mr. Perkins has endeavored to produce the 
sulpho-acid of nitroso-naphthaline, thinking that 
if such a compound could be obtained, it would 
possess a purple color, because it would be an acid 
itself. But although sulphuric acid does dissolve 
it, forming a blue solution, yet no combination 
takes place. He also endeavored to produce this 
desired result by treating sulpho-naphthalamic acid 
with nitrous acid, but obtained only nitroso napli- 



NAPHTHALINE COLORS. 109 

thaline, the acid of the sulpho-naphthalmic acid 
having apparently separated. 

Naphthamein. 

Piria observed that naphthalamine and its salts 
produced blue precipitates, afterwards becoming 
purple, when brought in contact with perchloride 
of iron, terchloride of gold, nitrate of silver, and 
other oxidizing agents. This product of oxidation 
he terms naphthamein. It is prepared by adding 
a solution of perchloride of iron to a solution of 
hydrochlorate of naphthamein. This mixture gra- 
dually changes and becomes blue ; and after the 
lapse of a short time deposits a blue precipitate. 
This, when separated by means of a filter, is washed 
with water, which causes it to change in color, 
until a reddish brown purple. The filtrate from 
this substance contains proto-chloride of iron, and, 
according to Piria, chloride of ammonium. Xaph- 
thamein, when heated, fuses and decomposes, leav- 
ing a residue of charcoal behind. It is insoluble 
in water, sparingly soluble in alcohol, but more 
soluble in ether. It forms a blue solution with 
concentrated sulphuric acid, and is precipitated 
from this solution by means of water. Silk and 
cotton may be dyed with it, but the color of this 
compound is so inferior, as to render it useless as 
a dyeing agent. 

' 10 



110 NAPHTHALINE COLORS. 

Tar Red. 

This coloring matter was discovered by Mr. 
Clift, of Manchester, in 1853. It is obtained by 
exposing a mixture of the more volatile parts of 
the basic oils of coal-tar and hypochlorite of lime 
to the air for about three weeks. Of the pure 
coloring matter we know nothing, except that with 
tannin it forms an insoluble, or difficultly soluble 
substance. With different mordants it yields dif- 
ferent colors. It seems probable that this coloring 
matter is derived from pyrhole. 

J 
This substance, which is a beautiful blue dye, 
has been introduced within the last year. It was 
discovered by MM. Guinon, Mamas and Bonney, 
of Lyons, who keep the process for its preparation a 
secret. It is obtained from coal-tar, but from 
which of its numerous derivatives is not known. 
This coloring matter is a brittle, ancrystallizable 
body, possessing a coppery, metallic reflection. 
It is very difficultly soluble in water, but soluble 
in alcohol, producing a magnificent blue solution, 
having but a slight tinge of red. With concen- 
trated sulphuric acid it forms a blood-red liquid 
which, when poured into an excess of water, pre- 
cipitates the coloring matter unchanged. Dilute 
acids have no effect upon azuline. Its alcoholic 
solution, when mixed with an alcoholic solution 
of hydrate of potash, also changes to a dull red 



NAPHTHALINE COLORS. Ill 

color. This, when diluted with water, forms a 
purple liquid which is gradually restored to its 
original blue color by hydrochloric acid. With 
excess of ammonia, the solutions of azuline change 
to a reddish purple color. This ammoniacal solu- 
tion, when treated with sulphide of ammonium, 
gradually assumes a dull, yellowish brown color. 
Iodine destroys the color of azuline. In color it 
is not quite so fine as chinoline blue, though far su- 
perior to Prussian blue. 



112 APPLICATION OF COAL TAR COLORS 



CHAPTER XIV. 

APPLICATION OF COAL-TAR COLORS TO THE ART OF 
DYEING AND CALICO PRINTING. 

We cannot enter fully into this subject, because 
we do not feel sufficiently acquainted with the 
various operations of the dye house or print works 
to do so, and also because the technical details 
of dyeing and printing operations would not, we 
think, interest the reader. We, therefore, propose 
to speak of the different processes employed for 
dyeing and printing with coal-tar colors, in gene- 
ral terms only. 

Dyeing Silk and W 

Silk and wool can be dyed with all the coal tar 
colors, with the exception of the rosolates, tl 
fibres possessing in most cases a remarkable affi- 
nity, if we may so speak, for these coloring matters. 
Many of them, as aniline purple, and violine, are 
taken from their aqueous solutions so perfectly by 
these substances that the water in which they have 
been dissolved is left colorless; in fact, silk and 
wool take them up so rapidly that one of the great 
difficulties the dyer has to contend with, is to get 
the fibres dyed evenly. 



TO THE ART OF DYEING, ETC. 113 

To Dye Silk with Aniline Purple, Violine and 

Roseine. 
One process is applicable for dyeing silk with 
either of these coloring matters, and it is a very 
simple one. An alcoholic solution of the coloring 
matter required, is to be mixed with about eight 
times its bulk of hot water previously acidulated 
with tartaric acid, and then poured into the dye- 
bath, which consists of cold water slightly acidu- 
lated. After being well mixed, the silk is to be 
worked in it, until of the required shade. If a 
bluer shade than that of the coloring matter is 
required, a little solution of sulpho-indigotic acid 
may be added to the dye bath, or the silk may pre- 
viously be dyed blue with Prussian blue, or any 
other blue, and then worked in the dye-bath. 

To Dye SilJc with Futschine, Picric Acid, Chinoline 
Blue and Violet. 

This process is still more simple than the above, 
as it is simply necessary to work the silk in cold, 
aqueous solutions of these coloring matters. With 
futschine or picric acid, a little acetic acid may be 
used, but with chinoline colors, acids must be avoid- 
ed. With picric acid, a very clear green color maybe 
obtained by adding a little sulpho-indigotic acid 
to the dye-bath. We may mention that violine is 
not of such a fine color as that produced by aniline 
purple and indigo blue ; and also that roseine is 
not such a good color as futschine, or magenta. 

10* 



114 APPLICATION OF COAL TAR COLORS 

To Dye Silk with Azuline. 

The dyeing of silk with this coloring matter is 
far more difficult than with the preceding, requir- 
ing to go through two or three different processes. 
The difficulty, we believe, arises from the insolu- 
bility of azuline in water. The process generally 
employed is to work the silk in a solution of the 
coloring matter acidulated with sulphuric acid, and 
when of a sufficient depth, to raise the temperature 
of the dye bath to the boiling point, and work the 
silk in it again. After this, the silk is well rinsed 
in water until free from acid, and worked in a 
bath of soap lather; it is then again rinsed and 
finished in a dilute acid bath. 

To Dye Wool with Aniline Purple^ Violinc, Ro 
Futsclrinc, etc. 

This operation is generally conducted at a tem- 
perature of 5° or 6° Centigrade, and the dye-bath 
is composed of nothing but a dilute aqueous solu- 
tion of the coloring matter required. Acids should 
be avoided, or only a very small quantity used, as 
the resulting colors are not so fine when they are 
employed. 

Method of Dyeing Cotton with Colors of Coal T 

When aniline purple was first introduced, con- 
siderable difficulty was experienced in dyeing cot- 
ton so as to obtain a color that would resist the 
action of soap. Aniline purple is absorbed by 



TO THE ART OF DYEING, ETC. 115 



vegetable fibres to a certain extent, and very beau- 
tiful colors may be obtained by simply working 
cotton in its aqueous solution ; but when thus dyed 
the colors will not stand the action of soap. We 
have tried the use of tin and other mordants, but 
without any satisfactory result. 

In 1857, Mr. Puller, of Perth, and Perkins, sim- 
ultaneously discovered a process by which this col- 
oring matter could be fixed upon vegetable fibres, 
so as to resist the action of soap. This process is 
based upon the formation of an insoluble compound 
of the coloring matter with tannin and metallic 
base in the fibre. To effect this the cotton has to 
be soaked in a decoction of sumach, galls, or any 
other substance rich in tannin, for an hour or two, 
and then passed into a weak solution of stannate 
of soda, and worked in it for about an hour. It 
is then wrung out, turned in a dilute acid liquor, 
and then rinsed in water. Cotton thus prepared is 
of a pale yellow color, and has a remakable power 
of combining with aniline purple. 

The above process may be modified, for example: 
the stannate of soda may be applied to the cotton 
before the tannin ; and alum may be used in the 
place of stannate of soda. To dye this prepared 
cotton with aniline purple it is only necessary to 
work it in an acidulated solution of the coloring 
matter ; and when thus prepared the cotton will 
absorb all the coloring matter of the dye-bath, leav- 
ing the water perfectly colorless. It has been found 



116 APPLICATION OF COAL TAR COLORS 

that cotton thus prepared can be dyed with any 
coloring matter that forms insoluble compounds 
with tannin, therefore it is used for dyeing with 
roseine, violine, futschine, and chinoline colors. 

Cotton may also be dyed a very good and fast 
color by mordanting it with a basic lead salt and 
then working it in hot solution of soap to which 
aniline purple has been added. Oiled cotton, such 
as is used for dyeing with madder, is also used in 
dyeing these c Cotton simply oiled, and 

before mordanted with alum and galls, also com- 
bines rapidly with these coloring matters; but as 
the color of the prepared cotton is generally rather 
yellow, it interferes sometimes with the beauty of 
the result. Cotton is sometimes coated with albu- 
men, which is coagulated by the action of steam, 
and the albumen which covers the cotton dyed in 
the usual manner. We may mention that violine, 
roseine, futschine, and also the chinoline colors 
combine with unmordanted vegetable fibres, as 
well as aniline purple. Picric and rosolic acids 
are not applicable for dyeing cotton. 

Printing Calico with Chal Tar Colors. 

The process generally employed for printing 
with these coloring matters is simply to mix the 
coloring matters with albumen or lacterinc, print 
the mixture on the fibre, and then to coagulate 
the albumen or lacterine by the agency of steam. 
Mr. Perkins and Mr. Gray, of the Dalmonach 



TO THE ART OF DYEING, ETC. 117 

Print Works, discovered the first process of ap- 
plying these substances to fabrics in a different 
manner from the above. It consisted in forming 
a basic carbonate or an oxide of lead on those 
parts of the cloth which were to be colored, and 
then working the cloth thus prepared in a hot 
lather containing the coloring matter. Where the 
cloth was mordanted with the lead compound 
coloring matter was absorbed ; but when unmor- 
danted it was left white, because pure cotton is not 
dyed with these coloring matters in the presence 
of soap. This procss was intended for the appli- 
cation of aniline purple, for at the period of this 
discovery, the other coal tar colors were unknown. 
Colors, dyed by this process were very pure, but 
it had many disadvantages, which have caused it 
to be disused. Lately the process previously de- 
scribed for dyeing colors upon cotton prepared 
with tannin has been applied to calico printing. 
It consists in printing tannin in the fabric pre- 
viously prepared with stannate of soda, and then 
dyeing it in a hot dilute acid solution of the color- 
ing matter. By this means the parts of the fabric 
which are covered with tannin are dyed a deep 
color, but the other parts are only slightly co- 
lored. These are cleared by means of well known 
processes. These methods of applying these co- 
loring matters is also modified by printing a com- 
pound of the coloring matter required and tannin 



118 APPLICATION OF COAL TAR COLORS 

on the prepared cloth, instead of tannin only, and 
then steaming the goods. 

Method of Apply rag Aniline Green to Fabrics. 

This process is interesting as being the first 
example of the production of coal-tal colors on 
the fabric itself. 

The process is very simple. The design is to 
be printed on the cloth with a thickened solution 
of chlorate of potash, dried, passed through a solu- 
tion of an aniline salt, again dried, and allows 
hang in a damp atmosphere. In the course of 
two or three days, the color will be fully deve- 
loped. The color thus produced may be changed 
into a dark blue by the agency of soap or an al- 
kaline liquid. The quantity of aniline used in 
this process is very small. 

Application of N%troeo-naphtha 

If cloth is printed with a thickened solution of 
a salt of naphthalamine, dried, and then passed 
through a solution of nitrate of potash, nitroso- 
naphthaline will rapidly make its appearance as a 
reddish orange color, but unfortunately the color 
thus obtained will not resist well the action of s 

Of the numerous coloring matters of which we 
have briefly spoken, there are only few that are 
at present employed by the dyer and printer, 
namely; Aniline purple, Futschine, Picric acid and 
Azuline, but we think it probable that others of 



TO THE ART OF DYEING, ETC. 119 

them will soon be introduced, such as the Bleu de 
Paris ; and Nitro-phenylenediamine might be used 
for silk dyeing, as its color is good and it stand 
the action of light well. Unfortunately the chino- 
line colors though very beautiful are most fugitive. 
There has been an endeavor to introduce the chi- 
noline blue of late, but although a considerable 
quantity of silk was dyed with it at first, it is 
now scarcely used, because when exposed to the 
sun for two or three hours the dyed silk becomes 
bleached. Aniline purple resists the light best, 
futschine and alpha aniline purple soon fade, espe- 
cially on cotton. Aniline and bleu de Paris are 
not easily acted upon by light when on silk. 

When the coloring matters of coal tar were 
first discovered, there was a great fear that the 
workmen engaged in their manufacture would 
suffer in health. All we can say is, that during 
the few years Mr. Perkins had to do with this 
branch of manufacture, there has not been a single 
case of illness among the workmen, that has been 
produced by any operation carried on for the pro- 
duction of aniline purple. 



: 



120 ACTION OF LIGHT ON 



CHAPTER XV. 

ACTION OF LIGHT ON COLORING MATTERS FROM 
COAL TAR. 

We think it will interest the reader to give him 
an extract of a paper published by our celebrated 
master, M, Chovreul, on this subject. We trans- 
late it literally from the Obmpt 8 R ndus of the 
Academic d j of the 10th July, 

18G0, vol. li. 

Two coloring matters recently produced are of 
frequent use, one to dye violet, and the other 
red violet. Both are obtained from aniline. 
This basis, under the influence of hypochlor 
gives the viokl, and treated by the anhydrous 
bichloride of tin gives the './, or futsc, 

Any coloring matter cannot be compared to the 
Futschine for the bright intensity, and purity 

of the color. It dyes the silk in 1st red vi 
red violet, 5th viold, and you can raise a gam from 
the white till the 11th shade, from the shade 4th 
till the 8th, we have the color called rase. Car- 
thamine applied on silk gives, generally, colors 
from the 3d red violet to the red, it can be then 
two, three, four or five gams of my chromatic 



COLORING MATTERS FROM COAL TAR. 121 

circle comprised between the color of the Futschine 
and that of the carthamine, both applied on silk. 
Before the futschine, carthamine was used to give 
the finest rose, but it was a rose less violet, whilst 
futschine gives a rose to the 5th violet of the red 
violet, or the 1st red violet, ordinary color of the 
rose. 

The roses of cochineal are, for the brightness 
and intensity, to the roses of carthamine that these 
are to the roses of futschine. Ladies who like the 
rose must avoid to place themselves near those 
who wear the rose of futschine or cochineal, if 
they wear themselves the rose of carthamine. If 
thanks are due to the author of the discovery of 
futschine, it is not a reason to have this color ap- 
plied on silk used for curtains, tapestry, etc., for 
if futschine has the beauty of the rose it has also its 
fragility. It is enough of four hours of exposition 
to the sun, to have the silk dyed with futschine 
to become tarnish, turn vinous, and afterwards 
reddish. 

Futschine on cotton is not stable. A card of 
specimens of wool, silk, cotton, dyed with futs- 
chine and carthamine, shows that futschine applied 
on silks is inferior in stability to the carthamine, for 
the silk dyed with this latter has an orange color 
more sensible that the one dyed with futschine, 
which has a violaceous color, and, however, that one 
had been raised to the 8th shade, whilst the speci- 
men dyed with carthamine had been only to the 
11 



122 ACTION OF LIGHT OX 

6, 5tb shade. When the red violet of futschine 
is changed after four hours exposition to the sun, 
the red violet of cochineal has not changed after 
one week to the same exposition. Silk mordanted 
with alum and cream tartar and dyed in red 
violet, 9th shade, that is the shade above crimson, 
after an insolation of eight months has lost only 
3 shades. At last silk dyed in 1st red violet, 10th 
shade, with cream tartar and tin composition lost 
in the same length of time l-5th shade. 

I have demonstrated in 1837 the influence of 
oxygen atmospheric in about every case, which, in 
stuffs dyed with organic coloring matters, are dis- 
colorized by their exposition to the sun, in proving 
that the same can be kept several years in lumi- 
nous vacuo. I have demonstrated, in the same 
year, that, on the contrary, Prussian blue is do- 
colorized in luminous vacuo; it becomes first white, 
then brownish, and is recolorized by the contact 
of oxygen. To-day I present to the Academy 
results very different; they have been given by 
picric acid used in dyeing since about 20 years. 

Cold it gives to the wool, yellow, 8th shade; to 
the silk 2d yellow 5th shade. Boiling it gives to 
the wool the 3d orange yellow 9th shade, to the 
silk the 1st yellow 6th shade ; in both cases it 
does not fix to the cotton. It is very curious to 
follow the changes that the wool and silk expe- 
rience under the influence of luminous air; they 
are described in the following table : — 



COLORING MATTERS FROM COAL TAR. 



123 







Co/or o/ the Silk. 




After 6 days* insolation 


yellow 


9th shade 


fi 18 (i 






5th or. yellow 


9th « 


" 1 month 






4th " 


9-5th " 


« 2 « 






3d * 


9th " 


U 3 « 






3d " 


9-8th " 


u 4 » 






1st " 


7-5th u 


" 5 " 




i 


1st M 


7-5th ■ 


« 6 " 




i 


" l-10th 6-25th " 


n 8 u 




t 


5th " 2-10th 3d " 






Cole 


»r of the Wool, 




After 6 days 


1 insolation 3d orange yellow 9-5th shade. 


n 18 « 




II 


3d " 


9-5th u 


" 1 months' 


C| 


2d " 


10th u 


u 2 « 




u 


orange yellow 


10-5th u 


u 3 « 




II 


ii 


ci ii 


« 4 < 




II 


5th orange 


11th " 


u 5 < 




(( 


4th " 


10-75th " 


H g « 




N 


3d " 


10-75th u 


u 8 i 




u 


3d " 


11th " 



These results are curious when you compare 
them to the proceedings. This progression by 
which the wool in 8 months gained 2 shades in 
passing from the 5th orange yellow 9th shade, to 
the 3d orange 11th shade, that is, passing by 8 
gams towards the red. The silk, after gaining -i 
shades, almost near the red, has begun to descend 
from the 3d month. 

Reflections. 

This is an important question to know if in the 

trade the buyer is not exposed to pay very dear, 

a color beautiful without doubt, but having no 

stability whatever, in the quality of the tissue. 



124 ACTION OF LIGHT ON COLORING MATTERS. 

This inconvenience is a real one, and this reflec- 
tions have for object not to destroy but attenuate 
them. 

Industry is free to manufacture any kind of 
colors, except in the case of a special convention 
between the manufacturer and the buyer. 

The merchant cannot be responsible, but it is 
to the buyer to have the merchant indicate on 
his bill the name of the matter used to dye the 
stuff; by pxample if it is a crimson or a rose that 
the buyer wants sold, he will have the bill with 
the denomination of crimson or rose of cochineal. 
I speak here only for stuffs used in tapestry, and 
J do not refer to the rosea of futsehine and i 
thamine employ 

If buyers were knowing the difference which 
exists between stufls of the same color, but dyed 
witli different matters, we are certain that before 
long, our stores will not have other colors than 
those known to be solids ; and if in a public 
place, the public had on the eyes two c itive 

tables, one dye with all colors which have been 
exposed to the sun a certain length of time, and 
the other with the same colors kept in the dark, 
the public will be soon instructed of the extreme 
difference existing between colors, and this in- 
struction will be the best warrant to not be de- 
ceived in the trade of colors. We hope to see 
some enterprising houses establish such tables, 
and we are sure they will render a great service 
to the public at large. 



LATEST IMPROVEMENTS, ETC. 125 



CHAPTER XVI. 

LATEST IMPROVEMENTS IN THE ART OF DYEING. 
CHRYSAMMIO ACID — MOLYBDIC AND PICRIC 
ACIDS — EXTRACT OF MADDER. 

Chrysammic Acid. 

Lately a color prepared with aloes has been 
used to dye, and its fine properties deserve to attract 
the attention of dyers. Messrs. Sacc and Schlura- 
berger have given a great attention to this pro- 
duct. We shall give its preparation and its uses 
to dye as described by Schlumberger. 

Preparation of the Coloring Matter. 

In a retort of a capacity of 22 to 28 gallons, 
introduce 67 pounds of commercial nitric acid 
and add to it about 18 ounces of aloes of the best 
quality. Heat the retort in a water bath under a 
chimney, when nitrous vapors begin to disengage, 
take out the fire and introduce in the retort by 
small portions 10 lbs. of aloes. When all the 
aloes has been introduced and the disengagement 
of nitrous vapors has stopped, pour the whole in a 
flat dish and evaporate in paste in a sand bath, 
and terminate the evaporation to dryness in a 

11* 



126 LATEST IMPKOVK.MEXTS IN 

water bath. Put the mass on a filter and wash it 
several times with cold water and dry at a gentle 
heat. 

The product in dye is of about 66] per cent, of 
the aloes used. The cost for 2\ pounds are about 
$1.40. 

Dyeing of Wool with Chrysammic Acid. 

If you dissolve in a kettle full of river water, 
2 lbs. 12 ounces of aloes purple, that you boil 
and refresh, and introduce in this bath 34 pounds 
of well washed wool, this wool, after an hour of 
ebulliti(*n, takes a fine brown color. If the 
quantity of chrysammic acid is double, you obtain 
a fine velvet black. 

If you dissolve 1 pound 11 ounces of chry- 
sammic acid in water, to which you add 2,^ lbs. 
of calcined soda, you obtain a liquid of a very fine 
purple color, which after a few days is very 
intense, and which can communicate to 34 pounds 
of wool, by an ebullition of half an hour, a fine 
bluish color. The wool wants to be well washed; 
but do not require any mordant. If for the same 
quantity of wool you use the double of purple 
of aloes, you obtain a blue similar to the blue of 
indigo by the vat. 

If you neutralize the filtered liquor collected 
from the washings of chrysammic acid obtained 
by evaporation, with a paste of chalk, and you 
filter the neutralized liquor, you can obtain with 



THE ART OF DYEING. 127 

this liquor, several shades more or less light of 
olive green, according to the concentration of the 
bath. 

At last chrysammic acid receives again a very- 
important application, in the use of it to fix other 
colors which are not solid. 

If you add 6f lbs. of orseille and 9 ounces of 
purple of aloes dissolved in caustic soda, you 
obtain an orseille color on which air and light 
have no action. 

The extract of orseille found in the trade, com- 
municates to wool brighter colors than common 
orseille, but they are not solid. Mr. Schlumberger 
has found that in mixing 11J lbs. of this extract 
with 18 ounces of dry aloes purple, and leaving 
the mixture several days, the colors obtained are 
solid and kept all their beauty. 

Chrysammic acid then is one of the most solid 
colors that the wool dyer can find, and it deserves 
a more attentive study. 

Molyhdic and Picric Acid. 

1. It is only since a short time that molybdic acid 
is used in the art of dyeing and different modes 
for its preparation have been indicated. 

The molybdic acid can be prepared in the 
following manner. Melt together equal weights 
of molybdate of lead reduced to fine powder, with 
calcined soda, in an iron crucible, decant the 
formed molybdate of soda, then prepare with hot 



128 LATEST IMPROVEMENTS IN 

water a concentrated solution of this molybdate 
that you decompose by an excess of nitric acid, 
and you boil till the molybdic acid separates in 
the form of a fine yellow precipitate ; this precipi- 
tate is washed with water and at last dried. 

The molybdate of ammonia is prepared in the 
following manner: Introduce little by little in 
caustic ammonia, molybdic acid, as much as it can 
be dissolved. The dissolution of molybdic acid is 
accompanied by a disengagement of heat, and 
presents itself in the form of a light yellow color, 
which has a very strong ammoniacal smell, and 
must be kept out of the contact of the air. 

I give now the different processes to dye stuffs 
with these preparations. 

Dyeing of Silk. 

You can obtain a very dark blue in impreg- 
nating silk with molybdate of ammonia : you lei 
to dry, and pass in a bath of hydrochloric acid, 
and immediately, without washing, in a bath of 
chloride of tin, to develop the blue color; wash 
well and dry. You can obtain lighter shades in 
diluting the molybdate of ammonia with water. 
Silk impregnated with a solution of molybdate of 
soda, at 20° B., dried aud pass in hydrochloric acid 
and chloride of tin baths, takes a nice blue color. 
In diluting the molybdate of soda with water, you 
can obtain lighter shades. 

These colors are very solid to the light. 



THE ART OF DYEING. 129 

» Dyeing of Cotton. 

The color on cotton appears less fine than on 
silk. The finest and darkest blues are obtained 
with the molybdate of ammonia; but, if the bath 
is diluted with three times its volume of water, 
you have then a gray-blue. 

We have not the least doubt that before many 
years this substance will be used by all the pro- 
fession. 

2. Picric acid has been employed first by Mr. 
Guinon of Lyons ; France, in the dyeing of silk 
and wool. Its process, to manufacture it by treat- 
ing coal tar by nitric and sulphuric acids, he ob- 
tains a resinoid matter, which, dissolved in more 
or less water, gives the shade wanted. It is in 
this bath, heated at 105°, that he passes the silk 
without mordant, and he introduces it afterwards 
in the warm room, without washing, to fix the 
color. 

The process to prepare it consists in heating 
coal tar, and to introduce into it three times its 
weight of nitric acid ; that you let run in it by a 
small glass pipe: boil with the acid till in a syrupy 
consistence ; wash several times with cold water, 
and afterwards with warm water, to separate the 
acid from the resinoid matters, and evaporate it 
to dryness to obtain crystals. 

15J grs. of picric acid, dissolved in a sufficient 
quantity of water, could dye, in yellow, 2J 
pounds of silk. 



130 LATEST IMPROVEMENTS IN 

Silk cloths take in it a very fine shade, with- 
out alterating their brightness. The results are 
the same with wool. With potash the shades can 
vary till yellow orange. 

For more details on this acid, we refer to Chap- 
ter VII. 

Madder, 

Madder is one of the coloring matters which 
has been the most studied in these last ti: 
That plant has been submitted to many treat- 
ments in order to extract from it its pure coloring 
matter. Wc shall enumerate briefly some of the 
most important treatments which have been tried 
on this plant. 

Extract of Madder by Messrs. Julian and Rogiter. 

They operate on madder in powder; they shake 
it conveniently in large vats, with cold or hot 
water, deprived of calcareous salts. They run it 
in vat-filters. 

According to the colors they wish to obtain, 
they leave the madder thus in paste in the vat- 
filters from one to five days, according to the want 
or not of an alcoholic fermentation. This paste is 
then well pressed and carried into ovens to be dried. 
The water collected after the pressure is submitted 
to the alcoholic fermentation. 



THE ART OF DYEING. 131 

Extract of Madder by Koecklin. 

His process gives an extract of madder free of 
ligneous matters, and the colors obtained in dye- 
ing are as good and solid as madder itself. He 
rises the neutral organic oxides ; such as acetone, 
hydrate of methylene, alone or combined with 
alcohols or heterogenous substances. These oxides 
are used as solvents of the coloring matter. 

It is by maceration and expression that he sa- 
turates the solvent; the bath being saturated, he 
precipitates the coloring matters by water, i. e., 
till water does not produce any precipitate. The 
precipitate filtered and dried constitutes the ex- 
tract of madder. 

It is a known fact, that in the use of madder in 
dyeing, they utilize only two-thirds of the color- 
ing matter, the last is retained in the residuum. 
Mr. Schwarts tried many experiments, the object 
of which was to utilize this coloring matter, and 
he has not succeeded. The best process he found 
is the following: — 

He takes 7 pounds 14 ounces of commercial 
sulphuric acid, and reduces it at 60° B. ; after it is 
cooled, he adds to it 6| ounces of flour of madder, 
which is equivalent to 13 ounces of washed mad- 
der. He leaves to macerate half an hour and throws 
the whole on a flannel: the filtration is slow, and the 
filtrate is of a very dark orange color. He pours 
this liquid in half a gallon of water, which preci- 



132 LATEST IMPROVEMENTS IN AKT OF DJfEING. 

pitates all the coloring matter, and then filters a 
second time through a thick flannel cloth. The 
filtrate is an acid which marks 35° B. 

The two matters left on the filters are perfectly 
washed with water, dried and weighed, they give 
three ounces of residuum, with a tinctorial power 
equal to six ounces of madder, and half an ounce 
of extract, equal to fifteen ounces of madder. For 
the acid at 35°, it can be used again in bringing 
it at 60° by distillation. 



THEORY OF COLORING MATTERS, ETC. 133 



CHAPTER XVII. 

THEORY OF THE FIXATION OF COLORING MATTERS 
IN DYEING AND PRINTING.. 

There are two methods of coloring stuffs which 
must not be confounded with each othef. By one 
of these, the coloring matters, lakes, etc., are mixed 
with gums or varnishes to make them into a color 
which is applied to the stuff, and which, on drying, 
adheres to it. Whether these coloring matters 
are mixed with a fat varnish, drying oil, white of 
egg, the result is always the same ; but this opera- 
tion, which is purely mechanical, and which may 
be performed on every kind of fabric, will only 
occupy the printer's attention so far as relates to 
the discovering of that glutinous body which is 
most capable of rendering this or that colored sub- 
stance adherent to such or such fabric. By the 
other method the coloring matters, brought to the 
proper conditions, are deposited and then fixed 
on the goods in such a manner as to be incorpo- 
rated with the fibre, and only to be capable of being 
detached from it by the intervention of a more or 
less powerful chemical agent; but some of them 
— and in this number are several substances of the 
12 



134 THEORY OF THE FIXATION OF COLORING 

organic kingdom, such as indigotin, carthamin, 
curcumin, and among the mineral colors, the ox- 
ides of iron, chromium, lead, etc. — only require to 
be applied on the goods; whilst a greater number 
of others, such as madder, cochineal, Brazil apd 
Campeachy woods, quercitron, and weld, unite 
with the different fibres only by the co-application 
of auxiliaries, which arc designated by the name 
of mordants ; it is in consequence of this difference 
that all who have written on dyeing have divided 
coloring matters into those which adhere to the goods 
of themselves^ and those whi I Ly 

the co-application of mordants. 

To discover the cause in virtue of which the 
different colored bodies unite with the textile fil 
of cotton, wool, and silk, to such a degree as to 
form with them one body; to explain how it hap- 
pens that one and the same substance has not the 
same aptitude for each of these fibres — such is the 
question which first presented itself to the scien- 
tific men who devoted their attention to the appli- 
cation of colors, and the solution of which is more 
especially important to the art of dyeing, of which 
the printing of fabrics is but a particular case. 
IIellot and Le Pileur d'Apligny, Macqi 
Berthollet, BbbgmANX, and Ciievkeul, who 
are justly entitled to rank as high authorities on 
this subject, have given forth different opinions 
on this point. The first two saw in the fixation 
of the colors an the goods only B purely mecbani- 



MATTERS IN DYEING AND PRINTING. 135 

cal operation ; the last four, on the contrary, only 
an operation purely chemical. 

Of all chemists Mr. Chevreul is the one who has 
searched most deeply into this important matter, 
and in comparing the general phenomena of dye- 
ing with those which natural philosophers and 
chemists generally consider as dependent on mo- 
lecular forces, the causes of chemical action, he 
arrives at the conclusion, that the first are of the 
number of those which take place when two or 
more bodies are in contact and their combination 
is effected slowly. 

It appears therefore that whilst Hellot and 
d'Apligny attribute all the effects produced by 
coloring matter, to the existence in the fibres, of 
pores more or less numerous and spacious, in 
which the coloring matter lodges, all chemists 
repudiate this view, and trace the same effects to 
chemical affinity. 

Such were the notions entertained by scientific 
men on the causes of the adherence of coloring 
matters to the goods, when the views of Mr. 
Walter Crum were published. According to 
the experiments of de Saussure, experiments so 
full of interest and so well known, chemists were 
aware that charcoal absorbs gases without altering 
their nature, in proportions which vary according 
to the nature of these gases, its own nature, and its 
state of porosity. No one is now ignorant of the 
applications which are daily made of this body in 



136 THEORY OF THE FIXATION OF COLORING 

the arts, for decoloring syrups, by freeing them 
from different substances. It is in connection 
with this order of facts, and enlightened, more- 
over, by the theoretic works of the celebrated 
chemist of Berlin, that Mr. Crum proceeds to ad- 
duce arguments in favor of the ideas of Ilellot. 
He advances, in fact, after passing in review the 
different modes of action of porous bodies, that 
several dyeing operations depend on the capillary 
action described by de Saussure; and this opinion 
he bases chiefly on the result of the microscopic 
examination of the fibres of cotton, which was 
made by Mr. Thompson, of Clitheroe, and M. 
Bauer — this examination having established that 
these fibres are formed of transparent and gl 
like tubes, which, though cylindrical before their 
maturity, flatten, on the contrary, from end to 
end, as they ripen, and then present the aspect of 
two separate tubes. Mr. Crum thinks that, since 
the sides of these tubes permit water to | 
through, they must be porous; but he adds, that 
neither the form, nor even the existence of such 
lateral perforations have been capable of being 
discovered by the aid of the most powerful mi- 
croscope. This, as will be seen, is the hypothesis 
put forward by Le Pileur d'Apligny, presented 
under a new form, and with the reserve of a mind 
essentially experimental. This being assumed, 
the eminent Scottish manufacturer explains the 
fixation of the colors in the following manner. 



MATTERS IN DYEING AND PRINTING. 137 

He first admits that the mineral base of a madder- 
dyed color — oxide of iron or aluminium — treated 
with a volatile acid — acetic acid, for example — 
gives rise to a solution which, when impressed on 
the fabric, is there gradually decomposed in course 
^of time, abandoning its acid, just as it would be de- 
composed in similar circumstances without the inter- 
vention of the cotton; and if this base, deposited on 
the fabric, remains adhering to it so powerfully as 
to resist the action of the most perfect washing, it 
is because the solution, after having penetrated by 
the lateral openings into the interior of the tubes 
which compose the cotton, is there decomposed, 
and the oxide being set free in the narrow pas- 
sage where it is enclosed, can no longer be disen- 
gaged from it. When the cotton, then, composed 
of sacs thus lined with metallic oxide, passes into 
a madder-bath, or one of any other coloring mat- 
ter, the latter combines with the metallic oxide by 
a true chemical action to form a lake, or what is 
properly called a color. 

Such are, in few words, the principal considera- 
tions which this chemist brings to bear on the 
question. Persoz holds a different opinion, and 
proceeds to examine how far this theory, which, 
by the author's admission, has several points of 
resemblance to that of Hellot and Le Pileur 
d'Apligny, admits of being supported by the facts 
on which it is based. The following are Persons 
views on the subject: — 

12* 



138 THEORY OF THE FIXATION OF COLORING 



According to the first proposition, the acetate 
of alumina, for example, would be decomposed in 
presence of the goods, just as if it were free, and 
experience seems to him to be here opposed to 
such an assertion. lie does not dispute that this 
salt, free, or in presence of the goods, is composed 
of acetic acid and alumina, or basic acetate; but 
that, for equal quantities, and diffused over equal 
surfaces of cotton cloth, plates of glass, mica, or 
platinum, and dried, moreover, in the same condi- 
tions, this acetate gives up always the same quan- 
tity of alumina, is what he finds it impossible to 
admit. In fact, if the desiccation takes place at a 
temperature but little elevated, the quantity of the 
earth, taken from the acetate by the cotton, will 
be incomparably greater than that which would 
be liberated on the glass or mica plates; it must 
be concluded, therefore, that the textile fibre of 
the cotton exercises a powerful influence on the 
decomposition of the acetate of alumina. But if 
any doubt still exist as to the part which the fibre 
performs in the decomposition of a mordant, the 
subjoined fact ought, he thinks, to dispel tl 
A solution of cubical alum, submitted to sponta- 
neous evaporation, yields crystals of cubical ah nn ; 
but if one puts in it, for a certain time, stuiV 
silk and cotton, this same solution now furnishes, 
after undergoing a spontaneous evaporation, no- 
thing but octahedral crystals of alum, deprived as 






MATTERS IN DYEING AND PRINTING. 139 

it is by these stuffs of a notable portion of its 
base. 

The organic and inorganic kingdoms, espe- 
cially the former, furnish a great number of sub- 
stances which possess the property of dyeing 
stuffs, either constituting colors by themselves, or 
entering as elements into compounds of a more 
complicated nature; but, to receive an application, 
these substances, simple or complex, must unite, 
if not by themselves, at least by the intervention 
of a suitably selected body, two essential qualities : 
first, that of being insoluble or nearly so ; second, 
that of resisting as much as possible the destructive 
action of the air and the solar rays. The first of 
these qualities is indispensable; for if it be want- 
ing, there is coloration of the goods, but not dyeing, 
in the proper sense of the word; a simple washing 
with water suffices to discharge the color. The 
second is not essential in the same degree, since 
it is subordinate to the stability which is intended 
to be given to the colors applied to a fabric. 

Indigotin, carthamin, curcumin, oxide of iron, ' 
oxide of chromium, sulphide of arsenic, sulphide 
of antimony, are dyeing substances by themselves. 
When one interrogates experiment as to the 
means of making them adhere to the goods, so 
strongly as to constitute one body with them, it 
is found to be necessary either to form these co- 
lors on the stuff itself, by putting in presence of 
the latter the elements of which they consist, and 







. 



140 THEORY OF THE FIXATION OF COLORING 

one of which at least must be soluble, or, if these 
tints are previously formed, to make them enter 
into a soluble combination with which one im- 
pregnates the fabric to set them afterwards at 
liberty, in such a condition that they combine with 
the fabric in the nascent state, either as protoxide, 
which, by oxidizing in the air, passes by degrees 
into the state of sesquioxide, or in the state of 
sesquioxide at first. The color of sesquioxide of 
chromium ifi fixed only in the same conditions. 
Again, to make the sulphides of antimony and 
arsenic adhere, it is sufficient to apply to the 

dfl one of the saline and soluble combinat' 
of these bodies, then to de -e it by an i 

BO as to set them at liberty. The fixation of C 
thamine takes place under circumstances nearly 
similar. 

The greater part of coloring matters — nine- 
tenths at least — are not of a dyeing power by 
themselves, and only become BO by entering into 
a combination which has for its object, not only 
to give them the first quality essential to ev 
tint for being fixed, insolubility^ but oftencr also 
to make them contract a shade which they do 
not assume by themselves. The coloring matter 
of madder, for example, which is soluble in water, 
acquires the property of dyeing only in so far as 
it is combined with a body capable, in the first 
place, of forming with it an insoluble compound, 
ascertain fatty substances, the oxides of aluminum, 



MATTERS IN DYEING AND PRINTING. 141 

tin, iron, et cetera, and then making it contract the 
hue which one desires to obtain. 

The different dye woods do not dye better by 
themselves than madder; and they require, like 
it, to enter previously into a combination. 

Chromic acid itself, rich as it is in color, becomes 
a dyeing substance only so far as it forms part of 
a saline combination, which should present, along 
with the shade desired, the greatest possible insolu- 
bility. Even the alumina, which serves as a base 
to all the organic colors, is not capable of fixing 
the chromic acid. 

It is only in so far as they are formed on the stuffs 
themselves, that the dyeing compounds of this 
group become adherent to them. In any other 
case there is no dyeing, unless, as sometimes hap- 
pens, the combination becomes by slow degrees 
insoluble, either by itself — carthamin — or by the 
intervention of a suitable agent — catechu. Ex- 
perience proves, moreover, that of the two sub- 
stances which usually occur or co-operate to the 
formation of the color, it is that which is insoluble 
which should be fixed first on the fabric, and with 
the same precautions as if one were dealing with 
one of the substances which are of a dyeing nature 
when used by themselves. The dyer deviates 
from this rule, only in so far as the elements of 
the lake, happening to be equally soluble, and 
endued moreover with an equal inclination for the 
fibre of the stuff, render it a matter of indifference 



142 THEORY OF THE COLORING 

whether the latter be first impregnated with the 
one or the other: thus the colored combination 
which is formed by nut-gall and a ferruginous 
preparation, is rendered adherent either by first 
depositing the iron compound on the fabric, and 
afterwards passing the latter into a decoction of 
nut-gall, or by commencing with impregnating 
the stuff with this infusion, to pass it afterwards 
into a ferruginous preparation. 

This rapid glance at the formation and fixation 
of dyeing substances, will doubtless suffice to 
make it understood that the subject under con- 
sideration presents different orders of facts, which 
it is necessary not to confound. In the fixation 
of indigo, for example, there are, on the one hand, 
the formation of indigo-blue, and on the other, 
the adherence of the latter to tho stuff. The first 
of these facts enters into the phenomena of oxi- 
dation that are best defined ; the second into those 
of adherence or juxtaposition, which are con- 
founded more or less with the facts pertaining to 
the aggregation of similar particles. In the fixa- 
tion of the color of madder, and of all its con- 
geners, there are in like manner two orders of 
facts: the one which relates to the most clearly 
understood chemical actions — namely, the union 
of this coloring matter with the oxide, which is 
called in to give it, besides the insolubility neces- 
sary to it, the desired shade; the other, which 
consists in the juxtaposition and adherence to the 



MATTERS IN DYEING AND PRINTING. 143 

stuff, of the lake which it produces. So, in the 
fixation of chromic acid, considered as a coloring 
matter, it is necessary to distinguish between the 
formation of the colored saline compound which 
one wishes to obtain, and its fixation, properly 
speaking, on the fabric. There are, therefore, in 
all the operations of dyeing and of the fixation of 
the colors, certain phenomena, which, inasmuch 
as they belong to the most common chemical re- 
actions, cannot give rise to any discussion ; let it 
now be considered whether it be not possible to 
dissipate likewise all uncertainty in what concerns 
the others. 



144 PRINCIPLES OF THE ACTION OF 



. CHAPTER XVIIL 

PRINCIPLES OF THE ACTION OF THE MOST IMPORT- 
ANT MORDANTS. 

IIitiierto, the term mordant has been applied 
to every substance which possesses the twofold 
property of uniting, on the one hand, with the 
goods, and on the other with the coloring matters. 
From this, it might appear that the morda 
possess properties quite peculiar, whilst in reality 
it is not so. Placing one's self in the point of view 
which accords with the theory advanced by Per- 
fcoz, one sees in these bodies only the clem* 
the constituent principles, of a saline compound 
which forms on the fabric itself to become adhe- 
rent to it. 

Prom the fact that the colorable and colored 
principles all combine with the metallic oxides to 
form insoluble compounds, it would seem also 
that these last should all be capable of fulfilling 
the part of mordants, and, consequently, of be- 
coming the base of the colored lakes formed on 
ihe stuff. It is not so, however; the number of 
bodies which possess this property is very limited. 
They are, among the compounds of the inorganic 



THE MOST IMPORTANT MOKDANTS. 145 

kingdom, the oxides of aluminium, iron, chromium, 
and tin ; among the products of the organic king- 
dom, the modified fatty bodies. The Editor has 
already pointed out a resemblance of the oxides 
of aluminum, iron, and chromium among them- 
selves, observing that the volume of their equiva- 
lents is the same; considered under another re- 
lation, these three compounds are, of all the 
metallic oxides, those which exhibit in the highest 
degree the property of passing from a state in 
which they possess their full aptitude for com- 
bining, to an isomeric state in which they become 
indifferent in the presence of the most energetic 
agents. 

For a body to be capable of performing the 
part of a mordant, it is necessary, in accordance 
with the views already stated, that the dimensions 
of its molecules be in a simple ratio to those of 
the surface of the fibre, and that, being fixed on 
the fabric, it give rise to a colored compound, the 
faces of which, being also in a simple relation with 
those of the fibre, cause its adherence. 

All the mordants do not in the same manner 
render the colors adherent to the stuffs; some 
cause them to undergo only slight changes of 
shade, depending on the acid or basic character 
which the mordant performs, and especially on 
the dimensions of the colored molecule which is 
formed. Thus, let hydrate of lead, on the one 
hand, be deposited on a stuff, and on the other, 









146 PRINCIPLES OF THE ACTION OF 

hydrate of alumina, both colorless, but possessed 
of different properties, and let this stuff be passed 
into a bath of cochineal; the aluminous mordant 
will be dyed red, and the lead mordant a deep 
black. The same will be the case, and for the 
same reason, with hydrate of tin and hydrate of 
alumina, which, if fixed on a stuff and dyed in a 
madder bath, will give — the latter, a red inclining 
to rose-violet, the former, a red inclining to orange. 
The others, particularly the oxide of iron, oa 
the colorable or colored principle to previously 
undergo an alteration; for, if the iron oxide com- 
bined purely and simply with the coloring matter 
of the madder, for example, which in its state of 
isolation is of a clear brown or orange-yellow, one 
should obtain lakes of a clearer color than that 
which is peculiar to this oxide, whilst lakes are 
produced of which the shade varies from the most 
intense black to the most delicate lilac, according 
to the proportion of oxide on the stuff. 

The nature of the principal mordants being 
known, the first point to be investigated is this — 
whether it be a matter of indifference to employ 
one saline combination rather than another, to 
render their base adherent to the goods? There 
are, in this question, two points to be considered: 
the first is one which the manufacturer should 
never lose sight of in the operations by which he 
applies a mordant on the goods, namely, the che- 
mical part which this mordant, once fixed, ought 



THE MOST IMPORTANT MORDANTS. 147 

to fulfil in presence of the coloring matter. Sup- 
pose, for example, that instead of having set at 
liberty on the goods hydrated alumina in that state 
in which it has all its chemical properties, it has, 
in point of fact, been deposited thereon in that 
state in which it loses momentarily all its aptitude 
for combining — the operation will be a failure, and 
goods thus mordanted will not dye. The second 
point is this, namely, that the brightness and in- 
tensity of the color which is obtained from 
a mordant depend on the manner in which this 
mordant is set at liberty, and passes into the inso- 
luble state on the fibre, to be brought into imme- 
diate contact with it. Thus, let hydrate of alumina 
be prepared with every precaution, let one part 
of it be slowly dried, and another quickly, and 
there will be obtained, in the first case, a coherent 
mass of a horny aspect, in the second, a dull and 
opaque mass ; and these two pieces, immersed in 
a solution of coloring matter of pure madder, will 
be dyed, the one of a red almost brown, the other, 
a dull and pale red. It is important, therefore, to 
seek, among saline combinations, that which yields 
most easily to the goods the base which it contains, 
and which is required to perform the part of a 
mordant, by preserving to this base all its chemi- 
cal power, and the physical state most favorable 
to the reflection of the luminous rays. 



143 



MINOUri MORDANTS, 



CHAPTER XIX. 



ALUMINOUS MORDANTS. 






TflJ aluminous compounds which are used to 
deposit on stuffs the oxide of aluminum in the 
state in which it a at, by attracting 

to it and fixing the ; matter of a dye-bath, 

are of two lands. In o alumina is in the 

state of a base; in i it performs the part of 

an ac 

In the basic state) there are as mnny aldmin< 
salts as acids, but all of them cannot be employed 
•is mordants, those which are insoluble ar 
off, by the slightest wi from the stuff 

which they are applied ; such are the t sul- 

phate, the phosphate, tl ate, 

the borate of alumina, e which are 

soluble behave in three different manners: & 
are basic, or capable 90 by giving up 

a part of their acid, and therefore require to be 
only deposited on a fabric to yield to the fibre, 
either in the cold or with the aid of a temperature 
more or less elevated, all or part of the alumina 
which they contain: such are the pure or impure 
acetate of alumina, cubic alum, oxalate of alumina 



ALUMINOUS MORDANT 149 

the butyrate and the formiate. Others, either 
neutral or containing an excess of acid, are divi- 
ded into two groups ; 1st, the salts of alumina in 
which the oxide is not masked, and which, conse- 
quently, may always become mordants or yield 
their oxide to the goods when their acid is satu- 
rated with no base, or when, by the aid of another 
salt, by double decomposition, the formation of a 
new aluminous salt, insoluble and adherent to the 
stuff, is determined ; to this category belong the 
sulphate, the seleniate, the chlorate, the bromate, 
the iodate, the bi-phosphate, the bi-arseniate, the 
nitrate, the chromate, the chloride, the bromide, 
the iodide, and octahedral alum ; 2d, the salts of 
alumina of which the base is masked, and which, 
saturated by an oxide, or mixed with another salt, 
would never furnish to the fabric an aluminous 
compound, insoluble, adherent, and capable of 
attracting the coloring matter. It is in this group 
that the tartrate, the citrate, and the malate of 
alumina range themselves. Thus, with the excep- 
tion of these last three, it may be said that all the 
compounds of alumina can serve for mordants; 
with this difference, nevertheless, that some re- 
quire only to be deposited on the stuffy at a 
temperature more or less elevated, to fix their 
base upon it, while others would remain upon it 
indefinitely without giving up alumina to the 
fabric, if by the intervention of something the 
base did not become free and insoluble. This 

IS* 



150 ALUMINOUS MORDAK1 

will be better understood by repeating the follow- 
ing experiments of Persoz. After previously 
scouring with an acid from all foreign matters, 
the samples of calico, A, B, C, D, E, he impreg- 
nated — 

Sample A with a solution of acetate of alumina at G° Tv. 
dell; 

Sample B with a solution of nitrate of alumina in the pre- 
ling liquor, and marking 12° Twaddell ; 

Sample C with a solution of nitrate of alumina at 6° Twad- 
dell ; 

S&mple D with a solution of alum in an aoetata of alumina at 
3°, and mark , !l : 

Sample E with alum marking 9° Twaddell ; 

and these samples, dried at the same tempera; 
in the same conditions, then ri 
in distilled water, lastly dyed in a madder bath. 
were found as follows: — 

Sample A, charged with coloring matter of an 
intensity proportional to the quantity of oxide 
yielded to the fabric by the acetate. 

Sample B — though impregnated with a prepara- 
tion containing much more alumina — was dyed a 
much weaker shade, showing the influence of the 
nitrate which always renders the decomposition 
of the acetate a little more difficult. 

Sample 0, always colorless when the nitrate of 
alumina employed contained one equivalent of 
base for three equivalents of acid, and the cloth 
on which it was applied was entirely freed from 
the calcareous substances with which it is some- 



ALUMINOUS MORDANTS. 151 

times charged on coming from the operations of 
bleaching, which are always finished with washings 
in water. 

Sample D, of a shade less intense, by half, than 
that of sample A, so that the alum associated with 
the acetate of alumina was a pure loss in the pro- 
cess. 

Sample E, colorless like sample C, and in the 
same conditions. 

When other samples, A', B', C, D', E', were 
impregnated with the same solutions, but after 
being dried were passed into menstrua containing 
either bi-carbonate v of potash or soda, or the neu- 
tral arseniate of potash and a little chalk, or any 
other saturating body incapable by its nature of 
redissolving the aluminous compound which is 
formed ; and when, as in the preceding case, all 
the samples had been washed and passed into a 
madder bath, the following is the state in which 
they presented themselves : — 

Sample A' had a shade of a much higher tone 
than sample A. 

Sample B' was of a shade double the intensity 
of that of sample B. 

Sample C of the same shade and tone as sample 
A', while C was colorless, or very slightly tinted. 

Sample D' of a deeper dye than D, intermediate 
between those of A' and B'. 

Sample E' ; instead of being colorless as sample 



152 ALUMINOUS MORDANTS. 

E, had a tint the intensity of which was propor- 
tional to the alumina of the alum which was 6 

Chloride of alumina gives the same results as 
the nitrate. 

Oxalate of alumina presents an important pe- 
culiarity, which must be taken into consideration ; 
at the moment of its formation it has not the 
property to yield its basis to the goods, but by 
prolonged contact, or instantaneously by action of 
the steam, this salt undergoes a transformation, 
and giving a part of its basis to the goods, becomes 
a mordant. 

Alum is of all ingredients the most generally 
employed, and that which has been longest in 
use. The octahedral alum has always the pro- 
perty of yielding to the stuff all or part of the 
alumina it contains, when it has been previously 
saturated with acetate of lead, lime, baryta, &c., 
which, by double decomposition, gives sulphates 
more or less soluble and a proportionate quan- 
tity of acetate of alumina. 

Old Mobdanto. 
Red mordant, from 1760 to 1800. In 22 gallons 
of water, they dissolved, 

55.5 lbs. alum, to which they add 
5.5 " arscnious acid, 
5.5 " litharge, 
14.0 " acetate of lead, 
1.54 " sulphuret of antimony, 
1.54 a chloride of mercury, 
3.3 " carbonate of soda. 



ALUMINOUS MORDANTS. 153 

Other from 1800 to 1824. In 22 gallons of water, 
they dissolved, 

49.5 lbs. alum, and to this add 
5.0 " acetate of copper, previously dissolved in 
one quart of acetic acid, 
27.5 " chlorhydrate of ammonia ; 
24.2 " carbonate of potash, 
24.2 " " lime, 

19.1 " acetate of lead. 

New Mordants. 
Mr. D. Koechlin, in his memoir on red mor- 
dants, gives the composition of the three fol- 
lowing: — 

Mordant No. 1. 
In 22 gallons of water dissolve 
88.0 lbs. alum, 
8.8 " carbonate of soda, 
88.0 " acetate of lead. 

Mordant No. 2. 
In 22 gallons of water dissolve 
60.0 lbs. alum, 

6.0 " carbonate of soda, 
44.5 " acetate of lead. 

Mordant No. 3. 
In 22 gallons of water dissolve . 
44.5 lbs. alum, 

5.0 " carbonate of soda, 
29.7 " acetate of lead. 



154 ALUMINOUS MORDANTS. 

The following is the process to prepare these 
mordants : — 

In a tub containing the powdered alum, pour 
the quantity of warm water necessary to dissolve 
it, then add the carbonate of soda, and at last the 
acetate of lead. A precipitate of sulphate of lead 
is formed. Shake the whole for one hour without 
interruption, and afterwards from time to time 
only. When the mordant has cooled and the sul- 
phate of lead has deposited, decant the clear liquor 
and keep it in stoneware vess« 

It would seem, at first view, that in all 
lishments, it must exist a mother mordant with 
which all the others might I .red by dilul 

it more or less with water, and making additions 
to it of substances suitable for the different 
however, it is not the custom of dyers and calico 
printers who prefer to prepare several kinds of 
mordants, being guided by the following consider- 
ations: — 

1. There are a few shades for which a very 
strong mordant is required, or one demand'r 
greater quantity of acetate of lead than a mordant 
of mean density. 

2. This last, into the preparation of which less 
acetate of lead enters, keeps longer than a strong 
mordant, which soon, by decomposition in the 
cold, depositing more subacctate of alumina than 
the mordant of mean density, would not always 
give a constant result when diluted with water. 



ALUMINOUS MORDANTS. 155 

3. A strong mordant, in which the acid acetate 
predominates, would not suit in several styles of 
printing, especially in that which consists of two 
or three reds where mordants of different density 
are printed one on another, because then the mor- 
dants getting confounded together would produce 
less distinct tints. 

4. The mode of giving consistence to a mordant, 
or of thickening, varies according to the kind of 
printing for which it is intended, and an acid 
mordant cannot be inspissated so easily as another, 
with any of the substances which are employed 
for that purpose. 

5. A strong and acid mordant is less easily 
discharged by the operation of dunging. 

In many calico-printing works in the neighbor- 
hood of Paris and Eouen, they use for the prepa- 
ration of the red mordants, sulphate of alumina, 
which is now manufactured in pretty large quan- 
tities. As it occurs in commerce, it contains : — 

Centesimally. 

Sulphuric acid 33.178 

Oxide of aluminum .... 17.820 
Water 49.002 



100.000 

It requires, therefore, seventy-five parts of 
acetate of lead to effect its partial saturation, and 
one hundred and eighteen parts of this same salt 
to render the double decomposition complete, and 
in order that all the sulphuric acid may be pre- 



156 



ALUMINOUS MOKI>A 



cipitated in the state of insoluble sulphate of lead. 
Nevertheless, these proportions of acetate may- 
vary considerably, for, as has been already 
remarked, the composition of the sulphate of 
alumina is not always the same. It is certain 
that the commercial article contains different 
quantities of acid and of base, and the manufac- 
turer cannot exercise too much circumspection in 
the use of this salt, especially for certain kinds of 
printing. 

ML D, Korhlin prepares the red mordant with 
the sulphate of alumina by op in the fol- 

lowing manner : — 

To one hundred and ten parts of a solution of 
sulphate of alumina, marki 11 when 

it is hot, and 56 € when cold, h< nc hundred 

parts of acetate of 1 d in thirty pan 

water; a double decomposition takes place bet* 
these two salts, and a solution i id is 

obtained, marking 84° to 26°— the most con 
trated which can be obtaii 

There are print-works in which the RQ6 
replaced by an equal weight of acetate of !< 
but when one does not wish to thcr the 

one or the other, equivalent quantities of ac» 
of lime, baryta, or soda may be substituted, since 
2375 pounds crystallized acetate of load are repl* 

hj 

1600 pounds anhydrous acetate of baryta, Of l>y 
1708 " crystallized acetate of soda, <>r l>y 
1233 " anhydrous acetate of potash 



ALUMINOUS MORDANTS. 157 

'If commerce supplied the market with the 
acetates of baryta or lime in a state of purity, the 
manufacturer would find a great advantage in 
using them, because he would leave the sulphate 
of lime or of baryta, the product of the double 
decomposition, mixed with the mordant, and these 
salts would contribute as a mastic to the thickening 
of the color. 

Instead of making the mordants by the way of 
double decomposition, which always necessitates 
the employment of an acetate, the mordant of which 
M. D. Koechlin indicated the preparation has long 
been manufactured on the large scale, and the fol- 
lowing is the process employed: 1. Neutralize a 
solution of alum, saturated in the cold, with car- 
bonate of potash, which is added by degrees 
with agitation, till the flakes which are formed 
begin to be no longer redissolved. 2. Bring this 
neutralized solution to the boiling point, so as to 
cause the formation of basic sulphate of alumina, 
which is collected and afterwards treated with 
acetic acid, wherein it dissolves perfectly, espe- 
cially in the heat, furnishing one of the strongest 
and most reliable mordants that can be prepared 
and employed. But it would be too troublesome 
to make this preparation on a small scale and in 
the works themselves, since it would be necessary 
to throw away the water from which the basic 
sulphate of alumina had been separated, and along 
with this water the sulphate of potash, so that all 
14 



158 



ALUMINOUS MuKDANTS. 



the potash of the alum ; the whole of that which 
served for its precipitation, and lastly, a certain 
quantity of the alum itself would be lost. If, on 
the contrary, the fabrication of this product were 
conducted on the large scale in an alum factory, 
where the water more or less saturated with sul- 
phate of potash might enter again continually into 
a new operation, there would be no loss of alkali; 
the basic sulphate of tilumina produced would be 
constant in its composition, dissoh U in the 

acetic acid ; and in this case one would economize 
the whole of the potash of the alum, which 
might be turned to g ount, and all the 

oxide of lead, when the acetate of this b 
employ* 

Appll -The mordants of alumina are 

employed alone or with some other mordants, for 
the fixation of all coloring matters, which require 
an intermediate agent to constitute a color, and to 
become afterward adherent to the goo< 



FERRUGINOUS MORDANTS. 159 



CHAPTER XX. 

FERRUGINOUS MORDANTS. 

The ferruginous preparations, like aluminous 
ones, only perform the part of mordants so far as 
they are soluble, and cause a deposit of oxide of 
iron on the stuff. Iron presents several degrees 
of oxidation, and it is necessary to find, not only 
the saline combination which best gives up its 
base to the stuff, but further, that which possesses, 
in addition to this property, the degree of oxida- 
tion necessary to attract the coloring matters with- 
out injuring the goods. The fact must not be 
lost sight of, that, in depositing a ferruginous 
preparation on the goods, the iron may be com- 
bined either in the state of protoxide, which 
passes by little and little to the state of sesqui- 
oxide and even of ferroso-ferric oxide — Fe 3 4 ; 
or in the state of sesqui-oxide, which may be hy- 
drated, namely, in that in which it preserves its 
chemical condition, or anhydrous, exhibiting that 
modification in which it is, so to speak, unfit to 
perform any part; are lastly in the state of a 
subsalt or insoluble neutral salt. 



160 FERRUGINOUS MORDANTS. 

In a paper entitled, Employment of pyroligneous 
acid in some operations of the arts, and published in 
the Annales des arts et manufactures, M. Bosc exa- 
mines in what state of oxidation iron should exist 
on the goods to serve as a base for black. Ac- 
cording to this author, one should obtain on 
cotton a deep black tint, firm and brilliant, only 
in so far as use is made of a salt of iron with a 
base of black or protoxide, and the most favora- 
ble combination would result from the solution of 
the iron in acetic acid, because this acid, by the 
carbon which it contains, would prevent oxida- 
tion, and maintain the oxide at its inferior degree. 

Arriving at the same conclusions, in a very 
extended memoir which treats of the fixation of 
the mordants of iron on cotton goods, M. II. 
Schlumberger establishes, first, that the acetate 
of iron obtained by several processes gives re- 
sults very similar, and bases this proposition on 
the following experiments: — 

lie thickened with gum-water on the one hand, 
and with starch on the other, the following solu- 
tions of equal strength — 10° Twaddell — videlicet, 

The first, of acetate of iron obtained by the 
double decomposition of sulphate of iron and 
acetate of lead. 

The second, of acetate of iron produced from a 
solution of iron in acetic acid. 

The third, of acetate of iron produced by a 
solution of the metal in ordinary vinegar. 



FERRUGINOUS MORDANTS. 161 

The fourth, of acetate of iron prepared by means 
of partially purified pyroligneous acid. 

The fifth, of acetate of iron from which the tar 
had been separated by five minutes' boiling. 

The sixth, of crude acetate of iron containing a 
great excess of tar. 

The seventh, and last, of crude acetate of iron 
mixed with the purified salt. 

These compositions were printed in the same 
conditions on pieces of calico ; each resulting sam- 
ple was then divided in two, and exposed to the 
atmosphere, one-half for two days only, the other 
for ten, before being submitted to the operation 
of dunging, and passed into a madder-bath where 
all gave a very fine violet, intense and very rich. 

When an acetate is employed as a mordant, 
theory and practice direct that the proto-acetate of 
iron be applied, in preference to the goods, and 
this, by decomposing on the stuff, passes by slow 
degrees to the state of a basic salt, which oxidizes 
in the air ; and, as it was desirable to inquire into 
the circumstances in which this oxidation might 
be effected without danger to the fabric, M. H. 
Schlumberger turned his attention to the question, 
and relates the results of experiments which he 
made on the four ferruginous preparations which 
follow, some at 24° Twaddell, and others at only 
7°. 

1. Acetate of iron obtained directly from the 
solutions of iron in acetic acid. 

14* 



162 FERRUGINOUS MORDAXTS. 

2. Crude acetate of iron. 

3. Acetate of iron obtained by the double 
decomposition of acetate of lead and sulphate of 
iron. 

4. The same solution, but with an excess of 
acetate of lead added. 

After printing these different solutions, gum- 
med and not gummed, on as many samples as 
were necessary to study the different circum- 
stances of oxidation, he exposed some, in a place 
with a mean temperature, to a moist air and dif- 
fused light; others in a warm situation, dry and 
darkened; others in fine to the rays of the 
and to all the atmospheric variations; and Left in 
these different conditions the half of each of tl 
samples for six days, and the other half for 
twenty-one days; then he passed them all into 
dung, to be subsequently cleaned and dyed, after 
which he found — 

1. That the weakening of the stuff generally 
took place only in the samples on which the con- 
centrated ferruginous solutions had been print 
and that in one case only, this weakening 
remarked on the stuffs impregnated with a solu- 
tion marking 6° ; 

2. That the goods were weakened by any of 
the four mordants mentioned above; less, ^Jiow- 
cver, with the last, containing an excess of the 
acetate of lead ; 

3. That the pure mordants weakened the stuff 



FERRUGINOUS MORDANTS. 163 

much more than those which were thickened with 
gum, starch, or fecula ; 

4. That exposure to the solar rays promotes in 
a given time the injurious effect on the goods, to 
such a degree that weak mordants, which do not 
attack the calico in darkness or in a diffuse light, 
deteriorate it very powerfully in the sun ; 

5. That in all the cases the weakening of the 
fabric does not decidedly show itself till the third 
or sixth day, but that at this period it is nearly 
the same as after the twenty-first day of the con- 
tact of the mordant with the stuff; 

6. Lastly, that as the samples are passed into 
the dung at a boiling heat, or only at the tempera- 
ture of 122°, and according as, on taking them 
out of this bath, they are or are not dipped into 
a dilute solution of chlor-oxide of calcium, the 
deterioration of the fabric is more or less decided, 
that is to say, it is scarcely perceptible if the 
samples have been cleared in a dung-bath heated 
to 122°, and if they have not been passed into 
bleaching powder liquor ; and, on the contrary, 
it is always strongly marked when the same sam- 
ples have been passed into the dung at a boiling 
temperature, or immersed immediately in the 
chlor-oxide. 

After having thus shown, on the one hand, that 
this weakening of the fabric is due to the oxida- 
tion which takes place by reason of the quantity 
of protoxide which is deposited upon it, and on 



164 FERRUGINOUS MORDANTS. 

the other, that it is reduced to nothing when the 
mordants are weak, and is very marked when 
they are concentrated, M. II. Schlumberger ex- 
plains this by the consecutive effects of the com- 
bination of the protoxide with the fabric, I 
circumstance involving disengagement of heat 
and electricity. M. Persoz accounts for this phe- 
nomenon by the fact of the momentary production 
of ferric acid — FeO a — which, as he ascertained by 
direct experiment, destroys tli B with groat 

energy when it is I'rco iii their presence. 

It appears, from the researches of Schlum- 
berger, that if, for hat impressions m black or 
violet, use le of crude acetate of iron 

strongly charged with a tar which obstinately 
maintains the iron in the state of protoxide on 
the cloth, very bad results are obtained in the 
dyeing, whilst the same salt mixed with a certain 
quantity of acetate, prepared by the solution of 
iron in acetic acid, never gives any but good re- 
sults. 

To these two orders of facts— which demon- 
strate, the one, the inefficacy of a mordant 
energetically maintained in the state of protosalt, 
the other, on the contrary, the efficacy of the 
mordant which is capable of passing to a superior 
degree of oxidation — Schlumberger adds others, 
which he adduces as affording unequivocal proof 
that a too advanced oxidation is always hurtful. 

Thus, for example, after having steamed samp 



FERRUGINOUS MORDANTS. 165 

on which were printed mordants of violet and 
puce-color — mixture of iron and alumina — he 
remarked that these samples, when dyed and 
heightened, presented shades of a much more 
reddish tint than if the mordants had not been 
submitted to the action of the steam, which, 
nevertheless, appeared to him more hurtful to 
the puce mordants containing alumina, than to 
the black mordants with an iron base, and hence 
he concluded that this result is due to a more 
advanced oxidation ; but Persoz thinks that there 
is here a misapprehension as to the part performed 
by the steam, which does not, in his opinion, set 
up any phenomenon of oxidation, but simply a 
change of physical state due to the heat, which 
renders indifferent a certain quantity of the ox- 
ides of iron and aluminum that are fixed on the 
stuff, and produce in this case, mixed with the 
violet — the sesqui-oxide, a kind of brown, and 
alutaina, a less full shade. 

Other samples, impregnated in like manner 
with mordants, and dipped, some into a solution 
of bichromate of potash, others into a bath of 
bleaching powder diluted and heated to 10-±°, did 
not give better results ; the tints of the samples 
passed into the bichromate were even more red- 
dish than those of the specimens passed into the 
steam, which may be accounted for, when it is 
borne in mind that always when a stuff on which 
a protosalt is printed, is dipped into a solution of 



166 FERRUGINOUS MORDANTS. 

bichromate of potassa, there is a double decom- 
position, followed by deterioration, and cot 
quently the formation of a compound which may 
be represented by a certain quantity of sesqui- 
oxides of chrome and iron ; now, these acting as 
mordants, and the former producing brown shades, 
it is not surprising that one cannot obtain fine 
violets. 

As for the action of the chlor-oxide of calcium, 
it is very simple: it modifies the physical state of 
the sesqui-oxide without changing its composition. 

According to Mr. Mercer, the best iron mor- 
dant is the crude acetate — pyrolignite — properly 
made, free from tar, but containing all the ethereal 
oils and spirit, as also the deoxidizing coloring 
matter, which prevent the too rapid oxidation of 
the iron. This mordant, combined with a proper 
quantity of white arsenic — arsenious acid — so as. 
to form sesqui-arscnite of iron as oxidation pro- 
gresses and acetic acid evaporates, is the htiirht 
of perfection for lilacs and fine plate work. The 
English purple plate styles from this mordant are 
unequalled. 

To sum up, it may be affirmed, without fear of 
contradiction from experiment, that when solutions 
of iron obtained by acetic acid are applied on the 
stuff", with the view of making them perform the 
part of mordants, it is right that they be in the 
state of protoxide, in order that, the oxidation tak- 
ing place on the cloth, there may be formed a basic 



FERRUGINOUS MORDANTS. 167 

acetate which will preserve to the sesqui-oxide 
its chemical properties, and pass to the state of 
phosphate or arseniate in the operation of dunging. 
It is necessary that this oxidation be slow and 
progressive, for, if it is rapid, the risk of the stuff 
being deteriorated, or of the sesqui-oxide passing 
into that isomeric state in which it becomes, as it 
were, indifferent to chemical agents, is incurred. 

As for the other ferruginous compounds, all 
the acid salts are unfit to perform the part of mor- 
dants, while it is otherwise with the neutral salts, 
seeing that the protoxide which they contain, 
passing to the state of sesqui-oxide by absorbing 
the oxygen of the air, they no longer contain 
enough of acid to form a neutral salt, and con- 
sequently there is the formation of a basic salt 
which becomes fixed on the stuff. It is thus that ' 
one explains why the neutral protosulphate which 
remains on the calico yields to it always a certain 
quantity of its base, whereas, when it is acid, this 
phenomenon no longer presents itself. As for 
the sesquisalts, all those which, from any cause 
whatever, can pass into the state of basic salts, 
then become true mordants, capable of attracting 
coloring matters. 

When the iron is in contact with the calico in 
presence of moist air, it produces, by oxidizing, 
spots of rust, which become fixed on the cloth 
and attract the coloring matter. 

In the same circumstances the protosulphate pre- 



168 FERRUGINOUS MORDANTS. 

sents the same results, either, from the circum- 
stances that, passing into the state of sulphate, by 
an absorption of oxygen, it is immediately trans, 
formed into a basic salt by fixing a higher 
proportion of oxygen, or that it has directly the 
power of fixing by a double decomposition a certain 
quantity of coloring matter. 

The Alkaline Mordants of Iron. — Few, besides 
llaussmann, have employed as mordants alkaline 
ferruginous solutions. He dissolves iron, or the 
protosulphate gently in nitric acid, under which 
condition there was always the formation of an 
ammoniaoa] salt. The following directions explain 
the reaction. 



BPe -}■ 19NO* + 4IIO = 5(1 •'■) + NH,*NO*HD -| 

-nitrate oflr 

NO" + NO 



IrOA. Citric acid. Water. Bstqui-nitTftte of ir.'ii. K 

mouia. 



The liquor abstracted was afterwards saturr 
with carbonate of potash, which was poured in 
very cautiously. The precipitate which formed 
at first was soon redissolved by an excess of car- 
bonate of potash, giving rise to a double salt, 
which was decomposed by the alkaline oxide. 
llaussmann states that he uses this solution with 
success in many circumstances. 

Applications. — Those mordants are used alone 
or mixed with those of alumina. In the first ( 
they serve with the red coloring matters to pro- 



FERRUGINOUS MORDANTS. 169 

duce on the stuffs gray, lilacs, violets and blacks ; 
with the yellow they give grays, olives more or 
less deep, with a mixture of red and yellow, a 
multitude of shades, from clear gray to the deepest 
black. Associated with alumina mordants, the fer- 
ruginous give with red coloring matters, pure 
shades more or less intense ; with yellow, yellows 
more or less olive; with a mixture of red and 
yellow they give brown colors, dead leaves, rather 
mauve, &c, which vary indefinitely according to 
the respective proportions of the mordants of 
alumina and iron. 



15 



170 STANNIFEROUS MORDANTS. 



CHAPTER XXI. 

STANNIFEROUS MORDANTS. 

Tin, by uniting with oxygen, gives two oxm 
one which reacts as a powerful base, the oth 
an acid; both arc applicable as mordants. From 
all metallic compounds the stanniferous combina- 
tions arc those which adhere to the goods with 
the greatest energy. The choice between a stan- 
nous and stannic salt is determined by the nature 
of the goods, and by that of the colors that it is de- 
sired to fix upon them. It will here be sufficient 
to consider the conditions in which these com- 
pounds must exist. 

The compounds in which the oxjde of tin performs 
the part of a base are of two kinds ; some having a 
base of protoxide, and others of binoxide. The 
protoxide is the most generally used; it cannot 
be separated on the stuff without giving up to it 
a certain quantity of its base, seeing that, when 
treated with water, it undergoes a partial decom- 
position, and is transferred into an acid salt, 
which remains in solution in that medium, and 



STANNIFEROUS MORDANTS. 171 

into a basic insoluble compound, which adheres 
to the fabric. 

Instead of chloride of tin, Bancroft employed 
a solution of the protosulphate in hydrochloric 
acid, which decomposes more easily in presence of 
the goods. He prepares it in the following man- 
ner : On 22 lbs. of granulated tin, introduced 
in a stoneware vessel, he pours 36 lbs. of com- 
mercial hydrochloric acid free from iron, adds 
little by little to this mixture 16^ lbs. of sulphuric 
acid ; there is development of heat, the tin is 
attacked first with violence, but it dissolves more 
slowly in proportion as the liquor comes more 
concentrated. The mixture is heated in a sand 
bath till complete dissolution. The whole being 
left to cool, a saline mass is obtained which con- 
tains a slight excess of tin. The liquor is de- 
canted, the remaining metal is weighed to know 
how much has been dissolved, and the liquor is 
diluted with as much water that its weight may 
be eight times that of the tin dissolved ; that is to 
say, 160 lbs. for example, if there have been 20 
lbs. of tin dissolved. Among the compounds of 
binoxide of tin, there is a multitude of preparations 
which are employed as mordants or constituent 
parts of the latter which are applied on the goods, 
and which contained binoxide, either pure or mixed 
with protoxide. They are generally called Tin 
compositions. The following are some of them: — 



172 STANNIFEROUS MORDANTS. 

1st. 22 lbs. of tin in ribands are dissolved with 
precaution in a mixture of 
I iC nitric acid, 
120 " commercial hydrochloric acid. 

2d. 22 " granulated tin are dissolved in a 
mixture formed of 



44 " 


hydrochloric acid, 


44 " 


nitric acid in which has been pre- 




viously dissolved 


11 " 


hydrochloratc of ammonia. 


3d. 22 " 


tin in ribands are gradually d 




solved in 


17ft 4< 


nitric acid at 40° in which has been 




previously difl 


22 " 


chlorhydrate of ammonia. 


4th. 22 " 


tin are dissolved in 


22 " 


nitric acid at 62°, 


44 " 


hydrochloric acid, 


44 " 


water. 

• 


5th. 22 " 


protochloride of tin are dissolved in 




a mixture of 


35 M 


hydrochloric acid and 


I7h" 


nitric acid; 


or of 




17J " 


hydrochloric acid or 


15" 


nitric acid ; 


or lastly of 




11 M 


hydrochloric acid. 


L5 M 


nitric acid. 



STANNIFEROUS MORDANTS, 173 

6th. 22. lbs protochloride of tin are gradually 
dissolved in 
27J " nitric acid. 
Farther, in a mixture formed, 
7th. 22 lbs. nitric acid, and 

22 " hydrochloric acid, 
as much tin is dissolved as these acids can reduce, 
and then heat is applied to dissolve in this liquor 
previously decanted 

2.2 lbs. protochloride of tin. 
8th. 22 " tin are dissolved with caution in 
42 " nitric acid at 64°, 
33 " hydrochloric acid at 36° ; the solu- 
tion being effected, add 
5J s< acetate of lead. 

Lastly, protochloride of tin is dissolved b} r 
small portions at a time to the point of saturation 
in nitric acid at 66° or 68°. The resulting solu- 
tion has the consistence of a jelly. 

With reference to the Compounds in which Oxide of 
Tin performs the part of an Acid, 

These mordants are of frequent use ; they are 
prepared by dissolving protoxide of tin, or, for 
greater economy, protochloride, in hydrate of 
potash or soda. These bases form with chlorine 
alkaline chlorides, and the stannous acid set free, 
combines with the excess of base to form a solu- 
ble stannite. 

This compound has very little stability ; car- 
15* 



174 STANNIFEROUS MORDANTS. 

bonic acid of the air tends to decompose it, and an- 
other cause is the unstability of its molecules, the 
atom of protoxide is divided in two and is trans- 
formed in binoxide, and metallic tin like shows 
the following reaction : — 

2SnO ±s SnO 2 +Sn 

Apirtication of the tin mordants. — The tin mordants 
are rarely employed to obtain dyed colors on those 
called maddered; they are used to combat the 
effects of iron, or after the dyeing is effected, to 
transform by substitution a lake with a base of 
alumina into another lake with a stanniferous la 
These mordants figure in all the colors of i 
lion, and specially in 

Other mordants are used to fix colors on 
fabrics as compounds with a base of sesqui- 
oxide of chrome. But although the latter oxide 
is isomorphous with alumina, and sesquioxide of 
iron is susceptible of adhering to the goods, and 
attracting coloring matters, it gives rise, by its 
greenish gray shade, to lakes which are not clear 
in the colors. 

These compounds, as well as those of some 
other metallic oxides, not being in general use, 
do not require to be minutely discussed, and with 
reference to the fatty organic mordant which plays 
so important a part in the Turkey red, we refer to 
general works on the art of dyeing and calico 
printing. 



ARTIFICIAL ALIZARIN. 175 



CHAPTER XXII. 

ARTIFICIAL ALIZARIN. 

We have seen that the bi-nitro-naphthaline is a 
fecund spring of colored products; the action of re- 
ducing agents, such as the sulphurets, the stan- 
nous saltsdissolved in caustic potash, the cyanide of 
potassium, &c, give with this substance derivated 
products which are red, violet, blue and very rich. 
When the reducing agents are of an acid nature, 
such as a mixture of zinc and diluted sulphuric 
acid, iron filings and acetic acid ; the bi-nitro-naph- 
thaline is not alterated. 

If you make to act concentrated sulphuric acid 
on the crystallized bi-nitro-naphthaline, it is no 
chemical reaction. In heating the mixture at 
482° the bi-nitro-naphthaline is dissolved, and sul- 
phuric acid begins to act only after a long ebulli- 
tion. When this solution is diluted with water, the 
bi-nitro-naphthaline is precipitated unalterated; 
the same if you treat madder at 212°, by con- 
centrated sulphuric acid all the products are 
destroyed but one — the coloring principle — or 
alizarine. 



176 ARTIFICIAL ALIZARIN". 

The formula of alizarine is represented by — 

C 20 H 6 O 6 

that of the bi-nitro-naphthaline by — 
C ro H 6 (NO*) 2 

A reducing agent capable to take two molecules 
of oxygen, and change the nitrogen in ammonia, 
could probably change the bi-nitro-naphthaline in 
alizarine, and the experiment has confirmed that 
theory. The following process permits to prepare 
artificial alizarine: — 

Make a mixture of bi-nitro-nnphthaline and 
concentrated sulphuric acid, that you introduce in 
a large dish heated in a sand bath. By the action 
of heat the bi-nitro-naphthaline is dissolved in sul- 
phuric acid. When the temperature is at about 
392°, throw in it some small pieces of zinc; few 
minutes after it disengages sulphurous acid; half an 
hour after the operation is achieved. If you let fall 
a drop of the acid mixture in cold water, a to 
nificent red violet color is formed, due to the 
formation of artificial alizarine; sometimes the 
reaction is very energetic; if the quantity of zinc 
is too considerable, the sulphuric acid boils rapidly, 
and a large quantity of white vapors are disen- 
gaged. The zinc must be added by small portions 
at a time. 

When the reaction is achieved, dilute the liquid 
with eight or ten times its volume of water, and 
boil, few minutes after you filter. The artificial 



ARTIFICIAL ALIZARIN. 177 

alizarine deposit on form of a red jell. The other 
water is strongly colored in red, and contains a 
considerable quantity of alizarine in solution. 
This water can be used directly to dye. 
• In the preceding reaction the zinc can be sub- 
stituted by many other substances, such as tin, 
iron, mercury, sulphur, carbon, &c. The two 
following equations show the reaction : — 

C^H^NO 1 ) 2 + 12M + lSSO^HO = C :0 H'O 6 + 2(S0 3 NH 3 H0) 

Bi-nitro-naph- Alizarine. Sulphate of ain- 

thaliue. nionia. 

+ 1250^10 + 10HO + 4S0* 



Metallic Sulphate. 
V TF(N0 4 )2 + IOC + 14(S0 3 H0)= C*H 6 6 + 



Bi-nitro-naphthaline. Alizarine. 

2(S0 3 ,XH 3 H0) + 10CO 2 + 12 So* + 6H0 

In the first equation it is the metal which acts 
on sulphuric acid, in the second it is the carbon 
itself. 

This artificial alizarine has all the characters 
of the ordinary alizarine. The following table 
shows how the two coloring matters comport : — 



178 METALLIC HYPOSULPHITES AS MORDANTS. 



COLORING MATTER OF THE 
MADDER 

is precipitated in jell from its 
solutions, 

is sublimated between 41 £P 
and 4640. 

Little soluble in water, solu- 
ble in alcohol, ether, and a 
solution of alum, 

unalterable by sulphuric acid 
heated at 392 , hydrochloric 
acid; alterable by nitric 

soluble in caustic or carbonat- 
ed alkalies with a purple 
color. 

Theammoniacal solution gives 
purple precipitates with the 
Baltfl of baryta and lime. 



ARTIFICIAL 
RED MATTER 

is precipitated in jell from its 
solutions, 

is sublimated between 419^ 
and 4640. 

Little soluble in water, solu- 
ble in alcohol, ether, and a 
solution of alum, 

unalterable by sulphuric 
heated at 392 , hydrochloric 
a<-id : alterable by ni trio add, 

solul-l tic and carbo- 

nate. 1 alkalies with a blue 
violet color. 

The aininoiiiacal solution 

purple precipitates with the 

salts of baryta and lime. 



The elementary analysis gives — 

Carbon . . 63.26 . . 63.51 
Hydrogen . . 2,10 . . 2.30 
New studies deserve to be done on this inte- 
resting body, which is called 'to render important 
services in the arts of dyeing and calico printing. 
This new substance gives colors as good and 
solid as the carmine of madder for impression and 
fixation of colors by steam on mordanted cotton 
cloths. 



METALLIC HYPOSULPHITES AS MORDANTS. 179 



CHAPTER XXIII. 

METALLIC HYPOSULPHITES AS MORDANTS — DYER'S 
SOAK— PREPARATION OF INDIGO FOR DYEING 
AND PRINTING — RELATIVE VALUE OF INDIGO- 
CHINESE GREEN— MUREXIDE. 

Mr. E. Kopp, a short time ago, has introduced 
the use of metallic hyposulphites as mordants, 
and he has shown that their use is preferable to 
the acetate of the same base. The hyposulphite 
of lime is the one used to obtain the others, its 
fabrication is known by every chemist. 

Hyposulphite of Alumina. 

To prepare a solution of hyposulphite of alumina 
he decomposes 64.60 grains of sulphate of alu- 
mina (3(S0 3 )AP0 3 + 18HO), dissolves in water by 
75.66 grains of crystallized hyposulphite of lime; 
he filters and expresses the residue of sulphate 
of lime. The solution is clear, limpid, and kept 
very well to the air ; a solution of hyposulphite 
of alumina marking 1.20 contains as much alu- 
mina as a solution of acetate of alumina at 1.10 
of specific gravity. This solution can be thick- 
ened by gum, roasted starch, &e, 



180 METALLIC HYPOSULPHITES AS MORDAN1 

If you use alum, you find that 13 J- lbs. of alum 
are decomposed completely by 9 lbs. 2 ounces of 
hyposulphite of soda (S 2 2 NaO + 51IO), or by 9 
lbs. 3 ounces of crystallized hyposulphite of lime 
(S 2 2 CaO + 6HO). It follows that U lbs. of this 
last salt can take the place of 6 lbs. 12 ounces of 
acetate of lead. 

Hyposulphite of Protoxide of Iron. 

This salt can be obtained by the action of sul- 
phurous acidonprotosulphuretof iron. mixed with 
water, or by the decomposition of the protosulphate 
of iron by the hyposulphite of lime ; it must be kept 
out of the contact of the air. In dyeing it be- 
haves like the other iron mordants. 

Hyposulphite of Chrome. 

This salt is prepared like the corresponding 
salt of alumina. It must be prepared a short 
time before its use. 

Ilyposulplute of Tin. 

All stannous salts being acids when they arc 
mixed with an alkaline hyposulphite, they disen- 
gage hyposulphurous acid. With the salts of prot- 
oxide of tin, they form a stannous sulphuret or 
oxy-sulphuret which are precipitated with stan- 
noso-stannic ; this formation takes a certain time 
according to the concentration of the liqtu 



SOAP FOR DYERS. 181 

In using a salt of peroxide of tin, it is no precipi- 
tation of tin in the liquors. The above observation 
shows that infusing hyposulphites, you must avoid 
mixing with a stannous salt, but always use a 
stannic salt or a mixture of them both. 
This salt gives a very good mordant. 

SOAP FOR DYERS. 

This soap is composed of — 

Ordinary oil or fatty body . 180 lbs. 

Palm oil 11 J" 

Spirit of Turpentine . . 33| " 

In all 225 " 

Dyers add to it from 5 to 6 quarts of lye of potash 
at 5° ; and 18 to 20 quarts of lye at 22°. The 
coction of the soap lasts twelve hours. 



16 



182 



PKEPARATION OF INDIGO Full 



PREPARATION OF INDIGO FOR DYEING AND 
CALICO PRINTING. 

Take 2 qts. of a paste containing about 2 lbs. 
of indigo in fine powder, mix with it 2 qts. of 
glucose prepared with rice starch. Take after- 
wards 2| lbs. of slacked lime diluted with water, 
that you mix with the glucose and indigo, add 
then 2 lbs. of solid caustic soda and shake care- 
fully. This compound thus prepared is ready 
for impression which is executed by the ordinary 
process. To dye with this indigo mix together the 
materials, viz : indigo, glucose, lime, soda, let it 
work a certain length of time at the ordinary tem- 
perature, and introduce it in the vat ready for the 
dyeing. 

Relative value of indigo. 



Country. 


value 
in coloring 

mat tor. 


iu 100 


Wafpr 
in LOO 


Indigo 


of East India 


. 68. 


4.5 


5.0 


ci 


M 


. 66. 


5.8 


6.0 


CI 


M 


. 64. 


S.l 


8.0 


ii 


II 


. 54. 


11.0 


7.0 


ii 


II 


. 51.5 


7.2 


7.5 


H 


II 


. 54. 


3.6 


7.0 


II 


CI 


. 45. 


14.0 


8.4 


Spanish Indigo 

II M 


. 55. 
. 50. 


12.3 
13.0 


6.0 
7.0 


II 


M 


. 44.5 


19.0 


5.5 


II 


CI 


. 28. 


33.4 


4.5 


Bengal 
n 




. (34. 
. 47. 


5.0 


4.0 
5.0 



DYEING AND CALICO PRINTING. 183 



Benares 




. 


45. 


20.7 


8.4 


Guatemala 




. 


50. 


16.0 


6.5 


Madras 




. 


41. 


10.6 


6.7 


Oude 




, . 


46. 


6.3 


8.5 


Caraccas 




, . 


52.5 


• 16.2 


6.4 


Madras 




. 


35. 


33.3 


6.0 


Java 




, 


63.5 


5.4 


4.8 


Bengal 




. 


59.5 


7.5 


5.0 


u 




, . 


56. 


11.0 


5.3 


u 




, 


45.5 


14.0 


7.2 


tt 




. . 


24. 


44.0 


4.4 


Manilla 




• 


35.5 


28.0 


5.0 




China Green. 







Mr. Charvin has extracted from the Rhamnus 
caiharticus a green coloring matter similar to the 
Chinese green (green indigo) but less costly. 
This product is in irregular plates with a variable 
aspect, according to the thickness of the plate. 
Like the Chinese Lo-Kao this product seems to 
be a lake, that is, a combination of an organic 
substance with an earthy matter. Gradually heated, 
it lost first water without any sublimate product ; 
in burning, it left a considerable quantity of ashes. 
The following is the result of a comparative ex- 
periment done at the same time with that product 
and the Io-Kao } with the analysis of Mr. Persoz : — 





Green. Charvin. 


-Chinese. 


Chinese 
by Persoz 


Water -. . " . 


13.5 


9.5 


9.3 


Ashes 


33. 


28.5 


28.8 


Coloring matter 


53.5 


62. 


61.9 



100.0 100.0 100.0 



184 PREPARATION OF INDIGO FOR 

Mr. Persoz defines the lo-Kao "a lake formed 
by cyanine, having for base phosphated magnesia, 
alumina, and oxide of iron." In Mr. Charvin's 
process, lime is only found, mixed with a little 
alumina and silica without phosphoric acid, but 
the coloring matter is the same in the two pro- 
ducts. The chemical reactions of Mr. Charvin's 
green are similar to the Chinese lo-Kao. 

Preparation. — In a kettle containing boiling 
water he puts 2 pounds of Rhammis cai/iarticus 
bark; a few minutes after a pink skim is produced. 
lie then puts the whole into an earthen jar, well 
covered, and then allows it to rest till next day. 
The liquid is yellowish ; it is decanted and lime 
water added to it, which produces a change of 
color; it turns reddish-brown, the liquid is put in 
jars — very little in each one — and the whole is ex- 
posed to air and light. The reddish-yellow color 
is modified and takes a green shade; little by little 
the green color becomes more general, and is then 
deposited in plates. All the liquids are mixed 
together and carbonate of potash is added ; a 
green precipitate is produced; he leaves it to de- 
posit, decants the liquid and collects the precipi- 
tate and dries it. The experiments of Mr. Char- 
vin prove, 

1st. That his green coloring matter is of the 
same nature as the Chinese lo-Kao, and will dye 
silk in as beautiful a green as the lo-Kao. 






DYEING AND CALICO PRINTING. 185 

2d. This matter is extracted from an indige- 
nous plant, the Rhamnus catharticus. 

3d. That the process will permit to manufac- 
ture it for dyers at the price of $8.90 per pound. 

MUREXIDE. 

Murexide can be manufactured with guano or 
uric acid, the processes are different. 

Fabrication with Guano. 

The choice of a good guano is important, the 
one containing the most urate of ammonia is 
the best. In the best Peruvian guano we found 
at least 5 and the most 15 per cent, of uric acid. 

1. Treat the guano by hydrochloric acid to de- 
compose the carbonate and oxalate of ammonia, 
the carbona,te and phosphate of lime, thp phos- 
phates of ammonia and magnesia. This operation 
is done in a lead kettle. You heat the acid which 
marks 12° B. and you throw in it gradually the 
guano by small portions. 

2. Boil the mixture one hour, draw the liquid 
in wooden vessels, wash the deposit by decanta- 
tion. 

3. The guano after this treatment is thrown on 
large filters ; the product thus obtained contains 
from 42 to 45 per cent, of dry substance. 

4. It is in this product that exists the uric acid 

16* 



186 PREPARATION OF INDIGO FOR 

mixed with sand, gypsum, organic deposits, and 
extractive matters. 

5. In a porcelain dish put 6 pounds of this 
guano thus prepared with 1J pound of hydro- 
chloric acid at 24° B., carry the whole at 122°. 
Take the dish from the fire and pour in it little by 
little in shaking all time 7 ounces of nitric acid 
at 40° B.; be careful that the temperature does 
not rise above 143° and fall below 111°. 

6. The mixture is then diluted with an equal 
volume of water and filtered, wash the deposit with 
water, reunite all the solutions and precipitate by 
a saturated solution of chloride of tin. 

7. When the precipitate is well formed, decant 
the brown liquid and wash it with water containing 
hydrochloric acid. 

8. Throw the precipitate on a filter, dry it and 
expose it to vapors of ammonia which transform 
it into murexide. 

Preparation of Uric Acid contained in Guano. 

The guano is treated by hydrochloric acid as 
we have seen above. 

In a copper kettle of about 125 gallons put 96 
gallons of water, 10 lbs. of caustic soda, and the 
mass obtained by the treatment of 252 lbs. of 
guano by hydrochloric acid and well washed with 
water. 

Heat the mixture till boiling, shake all time 
and kept at this temperature for one hour. 



DYEING AND CALICO PRINTING. 187 

Add to it a milk formed with 2| lbs. or 3J lbs. 
of caustic lime, shake well, boil J of an hour, take 
the kettle from the fire and let it settle for 3 or 
4 hours. 

Decant, and in the clear liquid put some hydro- 
chloric acid to precipitate the uric acid. Wash 
this precipitate by decantation, collect it on a filter 
and dry it. 

When you have taken all the clear liquid from 
the kettle, put on the residue a quantity of water 
equal to the first used, add again from 6J to 7J 
lbs. of caustic soda ; operate as above except that 
for the clarification you use only from 19 ounces 
to 1\ lb. of lime. 

After this second treatment the guano is gene- 
rally free of uric acid ; however, it is good and safe 
to repeat the operation a third time with less soda 
and lime. 

The uric acid, such as it is, can be used immedi- 
ately to prepare Murexide. 

Fabrication of Murexide after the Extraction of 
Uric Acid. 

For 2 lbs. of uric acid you must use 2 lbs. 10 
ounces of nitric acid at 36° B. 

The acid is put in a dish which is kept in cold 
water ; then you throw the uric acid by portions 
in the nitric acid; the dose must not exceed one 
ounce at a time ; you must distribute all the uric 
acid in the mass with a porcelain spatula, and you 



188 PREPARATION OF INDIGO FOR 

must not add uric acid till the mixture has come 
at 80°. 

When all the uric acid has been added, you let 
cool, and then you heat the whole slowly in a sand 
bath; when the liquid begins to swell take out 
from the fire, and when the swelling has fallen back 
begin again. When you heat for the third time, 
raise the temperature at 230°, and then put in the 
bath 9 J- ounces of liquid ammonia at 21°B., which 
transforms the mixture into murexide. Leave the 
dish about 2 minutes on the sand bath, take it out 
and leave to cool; you found a kind of paste in 
the mixture which is known by the name of 
murexide in paste. 

To obtain it dry and pure, mix that paste with 
water, filter and wash well; the last washing must 
be done with ammonia diluted with water; dry in 
the oven the product left on the filter — it is the 
Dry murexide. 

Application. — Murexide can be applied for calico 
printing in powder or in paste. 

Impression with the Color. — In 9 gallons of boiling 
water dissolve 251 lbs. of crystallized nitrate of 
lead, let cool the liquid till 144°; dissolve first 
in it 5 lbs. of powdered murexide or 15 lbs. of 
murexide in paste, then 39 lbs. of powdered gum; 
when all is cold it can be used. The printing 
terminated, hang the stuffs in a damp place and 
you fix the purple by ammoniac gas, the same 
process you pass woollen stuffs to sulphurous acid. 



DYEING AND CALICO PRINTING. 189 

Passage of the Stuffs in the Bath of Sublimate. — 
The warm bath in which the tissues are passed 
after exposition to the ammoniacal gas is composed 
of 191 gals, of water and 2 lbs. 11 ounces of corro- 
sive sublimate. The tissues are passed in this bath 
and then in running water, then they receive the 
bath of acetate of soda. 

Acetate of Soda. — This bath is composed of 360 
gals, of water with 1 lb. of acetate of soda and 
1 lb. of chlorhydrate of ammonia ; the tissues are 
passed in for 20 minutes, then well washed and 
dried. 

This progress gives a very beautiful purple red, 
all the gradations of red and rose can be obtained 
with murexide — the colors obtained are very 
solid. 



INDEX. 



Aluming .... 
Aniline, history of 

properties of . 

direct preparation of 

artificial preparation of 

di-nitro . 



green 

purple 

to dye with 

green, to fabrics, method of application of 

oxalate 

Alryle-toluidine 

Art of dyeing, historical notice of the 

chemical principles of the 
Azuline . . 
Alkaline mordants of iron 
Alizarin, artificial 
Alumina, hyposulphite of 
Acetate of soda . 



B 



Benzole, preparation of 
properties of . 
. properties of the bi-nitro 
bi-nitro .... 



PAGE 

. 44 
. 60 
60, 61 
60, 64 
68 
99 



81 

113 

118 

67 

82 

25 

33 

110 

168 

175 

179 

188 



68, 69 
68, 71 
68, 73 
. 74 



192 



INDEX. 



PAGE 

Bleaching silk 37 

cotton 39 

Bleu de Paris 89 

Benzolic acid, sulpho- 72 

Boiling cotton 40 

silk 37, 38 

Bath of sublimate, passage of stuff in 189 

C 

Carminaphtha 

Chloroxynaphthalatc of ammonia 
Calico with coal tar colors, printing . 

Chloroxynaphthalic acid 

Coal tar, on the coloring matters produced by . 

history of the coloring mutters produced by 

distillation 

to the arts of dyeing and culico printing, appli- 
cation of 112 

colors, printing with 116 

Chloraniline, fori- G2 

Chlorophenic acid, tri- 62 

Chloranile 62 

Cotton • . . .33 

Cotton with colors of coal tar, to dye . . . 114 
Cotton with molybdic acid, to dye . . . .129 
Crysammic acid 125 

preparation 125 

Cumidine 65, 98 

Chrome, hyposulphite of 180 

China green 183 



106 

LOS 

116 

lol 

49 

49 

52 



D 

Distillation and rectification of coal tar, table of the 

products obtained by the 

Dyeing 



INDEX. 



193 



E 



Emeraldine 



Fibres, preparation of the textile .... 33 
Fixation of coloring matters in dyeing and printing, 

theory of the 133 

Futschine 92 

by action of bichloride of tin on aniline, pre- 
paration of 93 

by action of nitrate of mercury, preparation of 94 



G 



Guano, preparation of uric acid in 



18G 



H 



osulphite, metallic, as mordants . 


. 179 


of alumina .... 


. 179 


of protoxide of iron 


. 180 


of chrome 


. 180 


of tin 


. 180 


I 




niline 


. 97 



Improvements in the art of dyeing .... 125 

Iron, the alkaline mordants of 168 

Ind* -^paration of, for dyeing and calico printing 182 

relative value of 182 



Light on coloring matters from coal tar, action of . 120 

Lutidine G5 

17 



194 



INDEX. 



M 






Madder 


PAGE 
. 130 


extract of ..... 


. 130, 131 


Magenta 


. 02 


Holybdic acid 


. 121 


Mordants 


. 43 


aluminous 


. 148 


old 


. 1 H 


new 


. 153 


ferruginous 


. 159 


principles of the action of the most important 111 




. 17!) 


Metallic hyposulphites as mordants . 


. 179 


Murexide 


. 185 


fabrication of, after extraction of . 


. l-:, 




. L85 


application of 


. 


N 




Naphthamcin 


. 100 


Nitro-phonisic acid, tri- ..... 


. 64 


Nitro-benzole, preparation . 


. 


properties 


08, 73 


into aniline, transformation of . 


. 


by sulphide of ammonium, reduction of 


. 70 


by nascent hydrogen, reduction of . 


. 77 


by acetate of iron, reduction of 


. 70 


Nitro-azo-pheuylaminc .... 


. 99 


Ninaphthalamme 


. 10G 


Nitroso-phcnylinc 


. 98 


Nitro-phenyline diamine .... 


. 90 


Nitroso-naphthaline 


. 107 


application of . 


. 118 


Nitroso-phcnylinc 


u 






INDEX. 



195 



Perchloroxynaphthalic acid 
Picric acid . . . 
Picoline .... 
Preparation of nitro-benzole 

of binitro-benzole . 

of futschine 
Pyrrol .... 
Pyrrhidine .... 
Protoxide of iron, hyposulphite of 



PAGE 
. 104 

64, 99, 127, 129 
65 
73 
73 
94 
65 
65 
180 



93 



Q 

Quinoline 65 

R 

Red, tar 110 

Roseine 87 

to dye with 113 

Rosolic acid 101 



Scouring wool 


. 35 


Silk 


. 37 


Silk 


. 37 


Silk and wool with coal tar colors, dyeing . 


. 112 


with futschine, picric acid, chinoline blu 


9 and 


violet, to dye .... 


. 113 


with azuline, to dye .... 


. 114 


with molybdic acid, to dye 


. 128 


Singing cotton stuffs . . . ... 


. 39 


Stuffs, preliminary preparations of . 


. 39 


Stannous salt 


. 170 


Stannic salt 


. 170 


Soap for dyers 


. 181 


Sublimate, passage of stuffs in bath of 


. 189 


Soda, acetate of 


. 189 



196 



IXDEX, 
T 



Tar red 

Transformation of nitro-benzinc into aniline 

Toluidine . 

Tin .... 

oxide of, as a base 

protosulpliate of 

compositions of 

oxide of, as an acid 

mordants, application of . 

hyposulphite of 

U 
Ungumming silk 
One acid in guano, preparation of 



PAGE 
110 

TG 
5, 98 
170 
170 
171 
171 
L73 
171 



81 



Yiolinc 



to dye with 



W 



L13 



Wool 34 

Wool with aniline purple, violine, roseine, fatschine, 

to dye lit 

with chrysammic acid, dyeing .... 126 

X 

Xylidine 98 









.... -■-..,. 

,: ... 



i ■ 






